- Added solutions by Alexander Karelas.

13 files changed, 1025 insertions, 976 deletions

diff --git a/challenge-050/alexander-karelas/perl/ch-1.pl b/challenge-050/alexander-karelas/perl/ch-1.pl
new file mode 100644
index 0000000000..c9526d530b
--- /dev/null
+++ b/challenge-050/alexander-karelas/perl/ch-1.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/env perl
+
+use v5.28;
+use warnings;
+
+use Data::Dumper;
+
+my @intervals = ([2,7], [3,9], [10,12], [15,19], [18,22]);
+
+# solution
+@intervals = sort {$a->[0] <=> $b->[0]} @intervals;
+for (my $i = 0; $i < $#intervals; $i++) {
+    if ($intervals[$i+1][0] <= $intervals[$i][1] and $intervals[$i+1][1] > $intervals[$i][1]) {
+        $intervals[$i][1] = $intervals[$i+1][1];
+        splice @intervals, $i+1, 1;
+    }
+}
+
+print Dumper(\@intervals);
diff --git a/challenge-050/alexander-karelas/perl/ch-2.pl b/challenge-050/alexander-karelas/perl/ch-2.pl
new file mode 100644
index 0000000000..5673914c0a
--- /dev/null
+++ b/challenge-050/alexander-karelas/perl/ch-2.pl
@@ -0,0 +1,15 @@
+#!/usr/bin/env perl
+
+use v5.28;
+use warnings;
+
+my @L = (2, 6, 1, 3);
+
+# solution
+my @l = sort { $b <=> $a } @L;
+my $noble;
+for (my $i = 0; $i < @l and $l[$i] >= $i; $i++) {
+    $noble = $i if $l[$i] == $i;
+}
+
+say defined $noble ? "Noble integer is: $noble" : "There is no noble integer in this set";
diff --git a/stats/pwc-current.json b/stats/pwc-current.json
index b0dabb777a..05edcded1b 100644
--- a/stats/pwc-current.json
+++ b/stats/pwc-current.json
@@ -1,25 +1,28 @@
 {
-   "subtitle" : {
-      "text" : "[Champions: 4] Last updated at 2020-03-02 12:32:54 GMT"
-   },
-   "tooltip" : {
-      "pointFormat" : "<span style='color:{point.color}'>{point.name}</span>: <b>{point.y:f}</b><br/>",
-      "followPointer" : 1,
-      "headerFormat" : "<span style='font-size:11px'>{series.name}</span><br/>"
-   },
    "drilldown" : {
       "series" : [
          {
+            "name" : "Alexander Karelas",
             "data" : [
                [
                   "Perl",
                   2
                ]
             ],
-            "id" : "Dave Cross",
-            "name" : "Dave Cross"
+            "id" : "Alexander Karelas"
          },
          {
+            "name" : "Dave Cross",
+            "data" : [
+               [
+                  "Perl",
+                  2
+               ]
+            ],
+            "id" : "Dave Cross"
+         },
+         {
+            "id" : "Luca Ferrari",
             "data" : [
                [
                   "Raku",
@@ -30,40 +33,47 @@
                   2
                ]
             ],
-            "id" : "Luca Ferrari",
             "name" : "Luca Ferrari"
          },
          {
-            "id" : "Markus Holzer",
             "data" : [
                [
                   "Raku",
                   2
                ]
             ],
+            "id" : "Markus Holzer",
             "name" : "Markus Holzer"
          },
          {
-            "name" : "Yet Ebreo",
+            "id" : "Yet Ebreo",
             "data" : [
                [
                   "Perl",
                   1
                ]
             ],
-            "id" : "Yet Ebreo"
+            "name" : "Yet Ebreo"
          }
       ]
    },
+   "title" : {
+      "text" : "Perl Weekly Challenge - 050"
+   },
    "series" : [
       {
-         "name" : "Perl Weekly Challenge - 050",
          "colorByPoint" : 1,
+         "name" : "Perl Weekly Challenge - 050",
          "data" : [
             {
-               "name" : "Dave Cross",
+               "y" : 2,
+               "name" : "Alexander Karelas",
+               "drilldown" : "Alexander Karelas"
+            },
+            {
+               "y" : 2,
                "drilldown" : "Dave Cross",
-               "y" : 2
+               "name" : "Dave Cross"
             },
             {
                "y" : 4,
@@ -83,30 +93,35 @@
          ]
       }
    ],
+   "subtitle" : {
+      "text" : "[Champions: 5] Last updated at 2020-03-02 12:38:55 GMT"
+   },
    "xAxis" : {
       "type" : "category"
    },
+   "yAxis" : {
+      "title" : {
+         "text" : "Total Solutions"
+      }
+   },
    "legend" : {
       "enabled" : 0
    },
-   "title" : {
-      "text" : "Perl Weekly Challenge - 050"
+   "tooltip" : {
+      "followPointer" : 1,
+      "pointFormat" : "<span style='color:{point.color}'>{point.name}</span>: <b>{point.y:f}</b><br/>",
+      "headerFormat" : "<span style='font-size:11px'>{series.name}</span><br/>"
+   },
+   "chart" : {
+      "type" : "column"
    },
    "plotOptions" : {
       "series" : {
-         "borderWidth" : 0,
          "dataLabels" : {
             "format" : "{point.y}",
             "enabled" : 1
-         }
-      }
-   },
-   "yAxis" : {
-      "title" : {
-         "text" : "Total Solutions"
+         },
+         "borderWidth" : 0
       }
-   },
-   "chart" : {
-      "type" : "column"
    }
 }
diff --git a/stats/pwc-language-breakdown-summary.json b/stats/pwc-language-breakdown-summary.json
index 3118c6e397..459fd068c1 100644
--- a/stats/pwc-language-breakdown-summary.json
+++ b/stats/pwc-language-breakdown-summary.json
@@ -1,24 +1,31 @@
 {
    "xAxis" : {
+      "type" : "category",
       "labels" : {
          "style" : {
-            "fontFamily" : "Verdana, sans-serif",
-            "fontSize" : "13px"
+            "fontSize" : "13px",
+            "fontFamily" : "Verdana, sans-serif"
          }
-      },
-      "type" : "category"
+      }
+   },
+   "yAxis" : {
+      "min" : 0,
+      "title" : {
+         "text" : null
+      }
+   },
+   "chart" : {
+      "type" : "column"
    },
    "legend" : {
       "enabled" : "false"
    },
-   "subtitle" : {
-      "text" : "Last updated at 2020-03-02 12:32:54 GMT"
-   },
    "tooltip" : {
       "pointFormat" : "<b>{point.y:.0f}</b>"
    },
    "series" : [
       {
+         "name" : "Contributions",
          "data" : [
             [
                "Blog",
@@ -26,24 +33,23 @@
             ],
             [
                "Perl",
-               2063
+               2065
             ],
             [
                "Raku",
                1258
             ]
          ],
-         "name" : "Contributions",
          "dataLabels" : {
             "enabled" : "true",
-            "color" : "#FFFFFF",
+            "y" : 10,
             "rotation" : -90,
-            "format" : "{point.y:.0f}",
             "style" : {
                "fontFamily" : "Verdana, sans-serif",
                "fontSize" : "13px"
             },
-            "y" : 10,
+            "format" : "{point.y:.0f}",
+            "color" : "#FFFFFF",
             "align" : "right"
          }
       }
@@ -51,13 +57,7 @@
    "title" : {
       "text" : "Perl Weekly Challenge Contributions [2019 - 2020]"
    },
-   "yAxis" : {
-      "min" : 0,
-      "title" : {
-         "text" : null
-      }
-   },
-   "chart" : {
-      "type" : "column"
+   "subtitle" : {
+      "text" : "Last updated at 2020-03-02 12:38:55 GMT"
    }
 }
diff --git a/stats/pwc-language-breakdown.json b/stats/pwc-language-breakdown.json
index cdc9c24899..dc72c779ca 100644
--- a/stats/pwc-language-breakdown.json
+++ b/stats/pwc-language-breakdown.json
@@ -1,36 +1,9 @@
 {
-   "title" : {
-      "text" : "Perl Weekly Challenge Language"
-   },
-   "plotOptions" : {
-      "series" : {
-         "dataLabels" : {
-            "enabled" : 1,
-            "format" : "{point.y}"
-         },
-         "borderWidth" : 0
-      }
-   },
-   "chart" : {
-      "type" : "column"
-   },
-   "yAxis" : {
-      "title" : {
-         "text" : "Total Solutions"
-      }
-   },
-   "subtitle" : {
-      "text" : "Click the columns to drilldown the language breakdown. Last updated at 2020-03-02 12:32:54 GMT"
-   },
-   "tooltip" : {
-      "headerFormat" : "<span style=\"font-size:11px\"></span>",
-      "followPointer" : "true",
-      "pointFormat" : "<span style=\"color:{point.color}\">Challenge {point.name}</span>: <b>{point.y:f}</b><br/>"
-   },
    "drilldown" : {
       "series" : [
          {
             "name" : "001",
+            "id" : "001",
             "data" : [
                [
                   "Perl",
@@ -44,12 +17,10 @@
                   "Blog",
                   11
                ]
-            ],
-            "id" : "001"
+            ]
          },
          {
             "name" : "002",
-            "id" : "002",
             "data" : [
                [
                   "Perl",
@@ -63,10 +34,10 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "002"
          },
          {
-            "name" : "003",
             "data" : [
                [
                   "Perl",
@@ -81,10 +52,10 @@
                   9
                ]
             ],
-            "id" : "003"
+            "id" : "003",
+            "name" : "003"
          },
          {
-            "name" : "004",
             "data" : [
                [
                   "Perl",
@@ -99,10 +70,10 @@
                   10
                ]
             ],
-            "id" : "004"
+            "id" : "004",
+            "name" : "004"
          },
          {
-            "id" : "005",
             "data" : [
                [
                   "Perl",
@@ -117,6 +88,7 @@
                   12
                ]
             ],
+            "id" : "005",
             "name" : "005"
          },
          {
@@ -156,7 +128,7 @@
             "name" : "007"
          },
          {
-            "id" : "008",
+            "name" : "008",
             "data" : [
                [
                   "Perl",
@@ -171,9 +143,10 @@
                   12
                ]
             ],
-            "name" : "008"
+            "id" : "008"
          },
          {
+            "name" : "009",
             "data" : [
                [
                   "Perl",
@@ -188,12 +161,10 @@
                   13
                ]
             ],
-            "id" : "009",
-            "name" : "009"
+            "id" : "009"
          },
          {
             "name" : "010",
-            "id" : "010",
             "data" : [
                [
                   "Perl",
@@ -207,9 +178,11 @@
                   "Blog",
                   11
                ]
-            ]
+            ],
+            "id" : "010"
          },
          {
+            "name" : "011",
             "id" : "011",
             "data" : [
                [
@@ -224,10 +197,10 @@
                   "Blog",
                   10
                ]
-            ],
-            "name" : "011"
+            ]
          },
          {
+            "id" : "012",
             "data" : [
                [
                   "Perl",
@@ -242,11 +215,9 @@
                   11
                ]
             ],
-            "id" : "012",
             "name" : "012"
          },
          {
-            "id" : "013",
             "data" : [
                [
                   "Perl",
@@ -261,6 +232,7 @@
                   13
                ]
             ],
+            "id" : "013",
             "name" : "013"
          },
          {
@@ -282,7 +254,6 @@
             ]
          },
          {
-            "name" : "015",
             "id" : "015",
             "data" : [
                [
@@ -297,10 +268,10 @@
                   "Blog",
                   15
                ]
-            ]
+            ],
+            "name" : "015"
          },
          {
-            "name" : "016",
             "data" : [
                [
                   "Perl",
@@ -315,10 +286,10 @@
                   12
                ]
             ],
-            "id" : "016"
+            "id" : "016",
+            "name" : "016"
          },
          {
-            "id" : "017",
             "data" : [
                [
                   "Perl",
@@ -333,10 +304,10 @@
                   12
                ]
             ],
+            "id" : "017",
             "name" : "017"
          },
          {
-            "id" : "018",
             "data" : [
                [
                   "Perl",
@@ -351,10 +322,10 @@
                   14
                ]
             ],
+            "id" : "018",
             "name" : "018"
          },
          {
-            "id" : "019",
             "data" : [
                [
                   "Perl",
@@ -369,6 +340,7 @@
                   13
                ]
             ],
+            "id" : "019",
             "name" : "019"
          },
          {
@@ -391,7 +363,6 @@
          },
          {
             "name" : "021",
-            "id" : "021",
             "data" : [
                [
                   "Perl",
@@ -405,11 +376,11 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "021"
          },
          {
             "name" : "022",
-            "id" : "022",
             "data" : [
                [
                   "Perl",
@@ -423,9 +394,11 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "022"
          },
          {
+            "id" : "023",
             "data" : [
                [
                   "Perl",
@@ -440,11 +413,11 @@
                   12
                ]
             ],
-            "id" : "023",
             "name" : "023"
          },
          {
             "name" : "024",
+            "id" : "024",
             "data" : [
                [
                   "Perl",
@@ -458,12 +431,10 @@
                   "Blog",
                   11
                ]
-            ],
-            "id" : "024"
+            ]
          },
          {
             "name" : "025",
-            "id" : "025",
             "data" : [
                [
                   "Perl",
@@ -477,10 +448,12 @@
                   "Blog",
                   12
                ]
-            ]
+            ],
+            "id" : "025"
          },
          {
             "name" : "026",
+            "id" : "026",
             "data" : [
                [
                   "Perl",
@@ -494,10 +467,10 @@
                   "Blog",
                   10
                ]
-            ],
-            "id" : "026"
+            ]
          },
          {
+            "name" : "027",
             "id" : "027",
             "data" : [
                [
@@ -512,11 +485,9 @@
                   "Blog",
                   9
                ]
-            ],
-            "name" : "027"
+            ]
          },
          {
-            "name" : "028",
             "data" : [
                [
                   "Perl",
@@ -531,10 +502,10 @@
                   9
                ]
             ],
-            "id" : "028"
+            "id" : "028",
+            "name" : "028"
          },
          {
-            "id" : "029",
             "data" : [
                [
                   "Perl",
@@ -549,10 +520,10 @@
                   12
                ]
             ],
+            "id" : "029",
             "name" : "029"
          },
          {
-            "name" : "030",
             "id" : "030",
             "data" : [
                [
@@ -567,10 +538,10 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "name" : "030"
          },
          {
-            "name" : "031",
             "data" : [
                [
                   "Perl",
@@ -585,11 +556,10 @@
                   9
                ]
             ],
-            "id" : "031"
+            "id" : "031",
+            "name" : "031"
          },
          {
-            "name" : "032",
-            "id" : "032",
             "data" : [
                [
                   "Perl",
@@ -603,11 +573,11 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "032",
+            "name" : "032"
          },
          {
-            "name" : "033",
-            "id" : "033",
             "data" : [
                [
                   "Perl",
@@ -621,10 +591,11 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "033",
+            "name" : "033"
          },
          {
-            "name" : "034",
             "data" : [
                [
                   "Perl",
@@ -639,10 +610,12 @@
                   11
                ]
             ],
-            "id" : "034"
+            "id" : "034",
+            "name" : "034"
          },
          {
             "name" : "035",
+            "id" : "035",
             "data" : [
                [
                   "Perl",
@@ -656,12 +629,10 @@
                   "Blog",
                   9
                ]
-            ],
-            "id" : "035"
+            ]
          },
          {
             "name" : "036",
-            "id" : "036",
             "data" : [
                [
                   "Perl",
@@ -675,10 +646,10 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "id" : "036"
          },
          {
-            "name" : "037",
             "data" : [
                [
                   "Perl",
@@ -693,10 +664,11 @@
                   9
                ]
             ],
-            "id" : "037"
+            "id" : "037",
+            "name" : "037"
          },
          {
-            "id" : "038",
+            "name" : "038",
             "data" : [
                [
                   "Perl",
@@ -711,9 +683,10 @@
                   12
                ]
             ],
-            "name" : "038"
+            "id" : "038"
          },
          {
+            "id" : "039",
             "data" : [
                [
                   "Perl",
@@ -728,11 +701,9 @@
                   12
                ]
             ],
-            "id" : "039",
             "name" : "039"
          },
          {
-            "name" : "040",
             "id" : "040",
             "data" : [
                [
@@ -747,10 +718,12 @@
                   "Blog",
                   9
                ]
-            ]
+            ],
+            "name" : "040"
          },
          {
             "name" : "041",
+            "id" : "041",
             "data" : [
                [
                   "Perl",
@@ -764,11 +737,11 @@
                   "Blog",
                   8
                ]
-            ],
-            "id" : "041"
+            ]
          },
          {
             "name" : "042",
+            "id" : "042",
             "data" : [
                [
                   "Perl",
@@ -782,11 +755,9 @@
                   "Blog",
                   11
                ]
-            ],
-            "id" : "042"
+            ]
          },
          {
-            "name" : "043",
             "id" : "043",
             "data" : [
                [
@@ -801,9 +772,11 @@
                   "Blog",
                   10
                ]
-            ]
+            ],
+            "name" : "043"
          },
          {
+            "name" : "044",
             "data" : [
                [
                   "Perl",
@@ -818,11 +791,10 @@
                   10
                ]
             ],
-            "id" : "044",
-            "name" : "044"
+            "id" : "044"
          },
          {
-            "name" : "045",
+            "id" : "045",
             "data" : [
                [
                   "Perl",
@@ -837,10 +809,10 @@
                   11
                ]
             ],
-            "id" : "045"
+            "name" : "045"
          },
          {
-            "name" : "046",
+            "id" : "046",
             "data" : [
                [
                   "Perl",
@@ -855,7 +827,7 @@
                   10
                ]
             ],
-            "id" : "046"
+            "name" : "046"
          },
          {
             "name" : "047",
@@ -877,6 +849,7 @@
          },
          {
             "name" : "048",
+            "id" : "048",
             "data" : [
                [
                   "Perl",
@@ -890,11 +863,10 @@
                   "Blog",
                   11
                ]
-            ],
-            "id" : "048"
+            ]
          },
          {
-            "id" : "049",
+            "name" : "049",
             "data" : [
                [
                   "Perl",
@@ -909,15 +881,14 @@
                   11
                ]
             ],
-            "name" : "049"
+            "id" : "049"
          },
          {
-            "name" : "050",
             "id" : "050",
             "data" : [
                [
                   "Perl",
-                  3
+                  5
                ],
                [
                   "Raku",
@@ -927,49 +898,53 @@
                   "Blog",
                   2
                ]
-            ]
+            ],
+            "name" : "050"
          }
       ]
    },
+   "title" : {
+      "text" : "Perl Weekly Challenge Language"
+   },
    "series" : [
       {
-         "name" : "Perl Weekly Challenge Languages",
          "colorByPoint" : "true",
+         "name" : "Perl Weekly Challenge Languages",
          "data" : [
             {
-               "y" : 140,
                "name" : "#001",
-               "drilldown" : "001"
+               "drilldown" : "001",
+               "y" : 140
             },
             {
-               "name" : "#002",
                "drilldown" : "002",
+               "name" : "#002",
                "y" : 109
             },
             {
-               "drilldown" : "003",
+               "y" : 71,
                "name" : "#003",
-               "y" : 71
+               "drilldown" : "003"
             },
             {
-               "name" : "#004",
                "drilldown" : "004",
+               "name" : "#004",
                "y" : 91
             },
             {
-               "y" : 71,
                "drilldown" : "005",
-               "name" : "#005"
+               "name" : "#005",
+               "y" : 71
             },
             {
-               "name" : "#006",
+               "y" : 52,
                "drilldown" : "006",
-               "y" : 52
+               "name" : "#006"
             },
             {
-               "y" : 58,
                "name" : "#007",
-               "drilldown" : "007"
+               "drilldown" : "007",
+               "y" : 58
             },
             {
                "y" : 70,
@@ -977,19 +952,19 @@
                "drilldown" : "008"
             },
             {
-               "y" : 68,
                "name" : "#009",
-               "drilldown" : "009"
+               "drilldown" : "009",
+               "y" : 68
             },
             {
                "y" : 60,
-               "name" : "#010",
-               "drilldown" : "010"
+               "drilldown" : "010",
+               "name" : "#010"
             },
             {
-               "y" : 79,
+               "drilldown" : "011",
                "name" : "#011",
-               "drilldown" : "011"
+               "y" : 79
             },
             {
                "y" : 83,
@@ -1002,14 +977,14 @@
                "y" : 76
             },
             {
-               "y" : 96,
                "name" : "#014",
-               "drilldown" : "014"
+               "drilldown" : "014",
+               "y" : 96
             },
             {
-               "drilldown" : "015",
+               "y" : 93,
                "name" : "#015",
-               "y" : 93
+               "drilldown" : "015"
             },
             {
                "name" : "#016",
@@ -1023,18 +998,18 @@
             },
             {
                "y" : 76,
-               "drilldown" : "018",
-               "name" : "#018"
+               "name" : "#018",
+               "drilldown" : "018"
             },
             {
+               "y" : 95,
                "name" : "#019",
-               "drilldown" : "019",
-               "y" : 95
+               "drilldown" : "019"
             },
             {
-               "y" : 95,
                "name" : "#020",
-               "drilldown" : "020"
+               "drilldown" : "020",
+               "y" : 95
             },
             {
                "drilldown" : "021",
@@ -1042,9 +1017,9 @@
                "y" : 67
             },
             {
-               "name" : "#022",
+               "y" : 63,
                "drilldown" : "022",
-               "y" : 63
+               "name" : "#022"
             },
             {
                "drilldown" : "023",
@@ -1052,24 +1027,24 @@
                "y" : 91
             },
             {
+               "y" : 70,
                "name" : "#024",
-               "drilldown" : "024",
-               "y" : 70
+               "drilldown" : "024"
             },
             {
-               "drilldown" : "025",
                "name" : "#025",
+               "drilldown" : "025",
                "y" : 55
             },
             {
-               "name" : "#026",
                "drilldown" : "026",
+               "name" : "#026",
                "y" : 70
             },
             {
+               "y" : 58,
                "drilldown" : "027",
-               "name" : "#027",
-               "y" : 58
+               "name" : "#027"
             },
             {
                "y" : 78,
@@ -1077,29 +1052,29 @@
                "drilldown" : "028"
             },
             {
-               "name" : "#029",
+               "y" : 77,
                "drilldown" : "029",
-               "y" : 77
+               "name" : "#029"
             },
             {
-               "name" : "#030",
+               "y" : 115,
                "drilldown" : "030",
-               "y" : 115
+               "name" : "#030"
             },
             {
-               "name" : "#031",
+               "y" : 87,
                "drilldown" : "031",
-               "y" : 87
+               "name" : "#031"
             },
             {
-               "name" : "#032",
                "drilldown" : "032",
+               "name" : "#032",
                "y" : 92
             },
             {
-               "y" : 108,
                "name" : "#033",
-               "drilldown" : "033"
+               "drilldown" : "033",
+               "y" : 108
             },
             {
                "y" : 62,
@@ -1107,33 +1082,33 @@
                "drilldown" : "034"
             },
             {
-               "drilldown" : "035",
                "name" : "#035",
+               "drilldown" : "035",
                "y" : 62
             },
             {
+               "y" : 63,
                "drilldown" : "036",
-               "name" : "#036",
-               "y" : 63
+