Merge pull request #12928 from deadmarshal/TWC345

TWC345

11 files changed, 253 insertions, 0 deletions

diff --git a/challenge-345/deadmarshal/blog.txt b/challenge-345/deadmarshal/blog.txt
new file mode 100644
index 0000000000..eeaa7e644f
--- /dev/null
+++ b/challenge-345/deadmarshal/blog.txt
@@ -0,0 +1 @@
+https://deadmarshal.blogspot.com/2025/10/twc345.html
diff --git a/challenge-345/deadmarshal/go/ch1.go b/challenge-345/deadmarshal/go/ch1.go
new file mode 100644
index 0000000000..8d055ab731
--- /dev/null
+++ b/challenge-345/deadmarshal/go/ch1.go
@@ -0,0 +1,23 @@
+package main
+
+import (
+	"fmt"
+)
+
+func peakPositions(arr []int) []int {
+	res := []int{}
+	for i := 1; i < len(arr)-1; i++ {
+		if arr[i-1] < arr[i] && arr[i+1] < arr[i] {
+			res = append(res, i)
+		}
+	}
+	return res
+}
+
+func main() {
+	fmt.Println(peakPositions([]int{1, 3, 2}))
+	fmt.Println(peakPositions([]int{2, 4, 6, 5, 3}))
+	fmt.Println(peakPositions([]int{1, 2, 3, 2, 4, 1}))
+	fmt.Println(peakPositions([]int{5, 3, 1}))
+	fmt.Println(peakPositions([]int{1, 5, 1, 5, 1, 5, 1}))
+}
diff --git a/challenge-345/deadmarshal/go/ch2.go b/challenge-345/deadmarshal/go/ch2.go
new file mode 100644
index 0000000000..dae2c9a781
--- /dev/null
+++ b/challenge-345/deadmarshal/go/ch2.go
@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+)
+
+func lastVisitor(arr []int) []int {
+	res, seen := []int{}, []int{}
+	k := 0
+	for _, e := range arr {
+		if e != -1 {
+			seen = append(seen, e)
+			k = len(seen)
+		} else if k == 0 {
+			res = append(res, -1)
+		} else {
+			k--
+			res = append(res, seen[k])
+		}
+	}
+	return res
+}
+
+func main() {
+	fmt.Println(lastVisitor([]int{5, -1, -1}))
+	fmt.Println(lastVisitor([]int{3, 7, -1, -1, -1}))
+	fmt.Println(lastVisitor([]int{2, -1, 4, -1, -1}))
+	fmt.Println(lastVisitor([]int{10, 20, -1, 30, -1, -1}))
+	fmt.Println(lastVisitor([]int{-1, -1, 5, -1}))
+}
diff --git a/challenge-345/deadmarshal/java/Ch1.java b/challenge-345/deadmarshal/java/Ch1.java
new file mode 100644
index 0000000000..d3012c5f90
--- /dev/null
+++ b/challenge-345/deadmarshal/java/Ch1.java
@@ -0,0 +1,21 @@
+import java.util.List;
+import java.util.ArrayList;
+
+public class Ch1 {
+  public static void main(String[] args) {
+    System.out.println(peak_positions(new int[]{1,3,2}));
+    System.out.println(peak_positions(new int[]{2,4,6,5,3}));
+    System.out.println(peak_positions(new int[]{1,2,3,2,4,1}));
+    System.out.println(peak_positions(new int[]{5,3,1}));
+    System.out.println(peak_positions(new int[]{1,5,1,5,1,5,1}));
+  }
+
+  private static List<Integer> peak_positions(int[] arr) {
+    List<Integer> res = new ArrayList<>();
+    for(int i = 1; i < arr.length-1; ++i) {
+      if(arr[i-1] < arr[i] && arr[i+1] < arr[i]) res.add(i);
+    }
+    return res;
+  }
+}
+
diff --git a/challenge-345/deadmarshal/java/Ch2.java b/challenge-345/deadmarshal/java/Ch2.java
new file mode 100644
index 0000000000..25c25ff98a
--- /dev/null
+++ b/challenge-345/deadmarshal/java/Ch2.java
@@ -0,0 +1,28 @@
+import java.util.List;
+import java.util.LinkedList;
+import java.util.ArrayList;
+
+public class Ch2 {
+  public static void main(String[] args) {
+    System.out.println(last_visitor(new int[]{5,-1,-1}));
+    System.out.println(last_visitor(new int[]{3,7,-1,-1,-1}));
+    System.out.println(last_visitor(new int[]{2,-1,4,-1,-1}));
+    System.out.println(last_visitor(new int[]{10,20,-1,30,-1,-1}));
+    System.out.println(last_visitor(new int[]{-1,-1,5,-1}));
+  }
+  
+  private static List<Integer> last_visitor(int[] arr) {
+    List<Integer> res = new LinkedList<Integer>();
+    List<Integer> seen = new ArrayList<Integer>();
+    int k = 0;
+    for(int i =0; i < arr.length; ++i) {
+      if(arr[i] != -1) {
+	seen.add(arr[i]);
+	k = seen.size();
+      }
+      else if(k == 0) res.add(-1);
+      else res.add(seen.get(--k));
+    }
+    return res;
+  }
+}
diff --git a/challenge-345/deadmarshal/modula-3/Ch1/src/Ch1.m3 b/challenge-345/deadmarshal/modula-3/Ch1/src/Ch1.m3
new file mode 100644
index 0000000000..473ff745be
--- /dev/null
+++ b/challenge-345/deadmarshal/modula-3/Ch1/src/Ch1.m3
@@ -0,0 +1,43 @@
+MODULE Ch1 EXPORTS Main;
+
+IMPORT SIO,IntSeq;
+
+VAR
+  A1 := ARRAY[0..2] OF INTEGER{1,3,2};
+  A2 := ARRAY[0..4] OF INTEGER{2,4,6,5,3};
+  A3 := ARRAY[0..5] OF INTEGER{1,2,3,2,4,1};
+  A4 := ARRAY[0..2] OF INTEGER{5,3,1};
+  A5 := ARRAY[0..6] OF INTEGER{1,5,1,5,1,5,1};
+
+PROCEDURE PeakPositions(VAR A:ARRAY OF INTEGER):IntSeq.T =
+  VAR
+    S := NEW(IntSeq.T).init(NUMBER(A));
+    I:INTEGER := 1;
+  BEGIN
+    IF NUMBER(A) < 3 THEN RETURN NIL END;
+    WHILE I < NUMBER(A)-1 DO
+      IF A[I-1] < A[I] AND A[I+1] < A[I] THEN S.addhi(I) END;
+      INC(I);
+    END;
+    IF S.size() = 0 THEN S.addhi(0) END;
+    RETURN S
+  END PeakPositions;
+
+PROCEDURE PrintSeq(READONLY S:IntSeq.T) =
+  BEGIN
+    IF S = NIL OR S.size() = 0 THEN SIO.PutText("[]\n"); RETURN END;
+    FOR I := 0 TO S.size()-1 DO
+      SIO.PutInt(S.get(I));
+      SIO.PutChar(' ')
+    END;
+    SIO.Nl()
+  END PrintSeq;
+  
+BEGIN
+  PrintSeq(PeakPositions(A1));
+  PrintSeq(PeakPositions(A2));
+  PrintSeq(PeakPositions(A3));
+  PrintSeq(PeakPositions(A4));
+  PrintSeq(PeakPositions(A5))
+END Ch1.
+
diff --git a/challenge-345/deadmarshal/modula-3/Ch1/src/m3makefile b/challenge-345/deadmarshal/modula-3/Ch1/src/m3makefile
new file mode 100644
index 0000000000..643b33d043
--- /dev/null
+++ b/challenge-345/deadmarshal/modula-3/Ch1/src/m3makefile
@@ -0,0 +1,4 @@
+import("libm3")
+import("libsio")
+implementation("Ch1")
+program("Ch1")
diff --git a/challenge-345/deadmarshal/modula-3/Ch2/src/Ch2.m3 b/challenge-345/deadmarshal/modula-3/Ch2/src/Ch2.m3
new file mode 100644
index 0000000000..2cd2cb5560
--- /dev/null
+++ b/challenge-345/deadmarshal/modula-3/Ch2/src/Ch2.m3
@@ -0,0 +1,49 @@
+MODULE Ch2 EXPORTS Main;
+
+IMPORT SIO,IntSeq;
+
+VAR
+  A1 := ARRAY[0..2] OF INTEGER{5,-1,-1};
+  A2 := ARRAY[0..4] OF INTEGER{3,7,-1,-1,-1};
+  A3 := ARRAY[0..4] OF INTEGER{2,-1,4,-1,-1};
+  A4 := ARRAY[0..5] OF INTEGER{10,20,-1,30,-1,-1};
+  A5 := ARRAY[0..3] OF INTEGER{-1,-1,5,-1};
+  
+PROCEDURE LastVisitor(VAR A:ARRAY OF INTEGER):IntSeq.T =
+  VAR
+    Res := NEW(IntSeq.T).init(NUMBER(A));
+    Seen := NEW(IntSeq.T).init(NUMBER(A));
+    K := 0;
+  BEGIN
+    FOR I := FIRST(A) TO LAST(A) DO
+      IF A[I] # -1 THEN
+        Seen.addhi(A[I]);
+        K := Seen.size()
+      ELSIF K = 0 THEN
+        Res.addhi(-1)
+      ELSE
+        DEC(K);
+        Res.addhi(Seen.get(K))
+      END
+    END;
+    RETURN Res
+  END LastVisitor;
+
+PROCEDURE PrintSeq(READONLY S:IntSeq.T) =
+  BEGIN
+    IF S = NIL OR S.size() = 0 THEN SIO.PutText("[]\n"); RETURN END;
+    FOR I := 0 TO S.size()-1 DO
+      SIO.PutInt(S.get(I));
+      SIO.PutChar(' ')
+    END;
+    SIO.Nl()
+  END PrintSeq;
+  
+BEGIN
+  PrintSeq(LastVisitor(A1));
+  PrintSeq(LastVisitor(A2));
+  PrintSeq(LastVisitor(A3));
+  PrintSeq(LastVisitor(A4));
+  PrintSeq(LastVisitor(A5))
+END Ch2.
+
diff --git a/challenge-345/deadmarshal/modula-3/Ch2/src/m3makefile b/challenge-345/deadmarshal/modula-3/Ch2/src/m3makefile
new file mode 100644
index 0000000000..78802242fe
--- /dev/null
+++ b/challenge-345/deadmarshal/modula-3/Ch2/src/m3makefile
@@ -0,0 +1,4 @@
+import("libm3")
+import("libsio")
+implementation("Ch2")
+program("Ch2")
diff --git a/challenge-345/deadmarshal/perl/ch-1.pl b/challenge-345/deadmarshal/perl/ch-1.pl
new file mode 100644
index 0000000000..a6c90d204a
--- /dev/null
+++ b/challenge-345/deadmarshal/perl/ch-1.pl
@@ -0,0 +1,22 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use Data::Show;
+
+sub peak_positions{
+  my ($arr) = @_;
+  my @res;
+  foreach my $i(1..$#$arr) {
+    if($arr->[$i-1] < $arr->[$i] && $arr->[$i+1] < $arr->[$i]) {
+      push @res,$i
+    }
+  }
+  @res
+}
+
+show peak_positions([1,3,2]);
+show peak_positions([2,4,6,5,3]);
+show peak_positions([1,2,3,2,4,1]);
+show peak_positions([5,3,1]);
+show peak_positions([1,5,1,5,1,5,1]);
+
diff --git a/challenge-345/deadmarshal/perl/ch-2.pl b/challenge-345/deadmarshal/perl/ch-2.pl
new file mode 100644
index 0000000000..18aeb76c47
--- /dev/null
+++ b/challenge-345/deadmarshal/perl/ch-2.pl
@@ -0,0 +1,28 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+use Data::Show;
+
+sub last_visitor{
+  my ($arr) = @_;
+  my (@res,@seen);
+  my $k = 0;
+  foreach my $i(0..$#$arr) {
+    if($arr->[$i] != -1) {
+      push @seen,$arr->[$i];
+      $k = @seen
+    } elsif ($k == 0) {
+      push @res,-1
+    } else {
+      push @res,$seen[--$k]
+    }
+  }
+  @res
+}
+
+show last_visitor([5,-1,-1]);
+show last_visitor([3,7,-1,-1,-1]);
+show last_visitor([2,-1,4,-1,-1]);
+show last_visitor([10,20,-1,30,-1,-1]);
+show last_visitor([-1,-1,5,-1])
+