Smalltalk, Java, C++, Node.js

4 files changed, 152 insertions, 14 deletions

diff --git a/challenge-147/cheok-yin-fung/blog.txt b/challenge-147/cheok-yin-fung/blog.txt
index 9b08363ef9..815ab13ca8 100644
--- a/challenge-147/cheok-yin-fung/blog.txt
+++ b/challenge-147/cheok-yin-fung/blog.txt
@@ -1,16 +1,24 @@
 This is the beginning of the semester of my PG dip in IT; and I have finished all exams and assignments from the previous semester. Somehow today I want to try to play with programming languages. While Mohammad has said, having fun is important in learning, now I try to do the Task 1 in different programming languages which I am fluent at least at the "sightseeing purpose", within 4 days.
 
 Target list:
-awk bash C++
+awk(?) bash(?) 
+
+C++
 Java Node.js Julia
 LISP PHP Perl Smalltalk
 Befunge-93 (if I have that mentality)
 
-Script done (last update: Fri Jan 14 03:25:06 2022): 
+Script done (last update: Fri Jan 14 13:19 2022 HKT): 
 1. Julia
 2. Perl
 3. Smalltalk
 4. Java
+5. C++
+6. Node.js
+
+Left:
+LISP
+Befunge-93
 >>>>
 The above content will be edited and put on https://e7-87-83.github.io/coding/challenge_147.html
 
diff --git a/challenge-147/cheok-yin-fung/cpp/ch-1.cpp b/challenge-147/cheok-yin-fung/cpp/ch-1.cpp
new file mode 100644
index 0000000000..dbfdff0aaa
--- /dev/null
+++ b/challenge-147/cheok-yin-fung/cpp/ch-1.cpp
@@ -0,0 +1,71 @@
+// The Weekly Challenge 147
+// Task 1 Truncatable Prime
+// g++ ch-1.cpp -o ch-1.o
+// Friday, January 14, 2022 PM01:15:37 HKT
+
+#include <vector>
+#include <cmath>
+#include <algorithm>
+#include <iostream>
+
+using namespace std;
+vector<int> ltp = {};
+vector<int> recent_ltp = {2, 3, 5, 7};
+vector<int> new_ltp = {};
+vector<int> primes = {2, 3, 5, 7};
+
+bool is_prime(int t) {
+    for (int k = 0; primes.at(k) <= sqrt(t); k++) {
+        if (t % primes.at(k) == 0)
+            return false;
+    }
+    return true;
+}
+
+
+
+void append_primes(int max) {
+    for (int can = primes.back()+1; can <= max; can++) {
+        bool good = true;
+        for (int k = 0; primes.at(k) <= sqrt(can) & good; k++ ) {
+            if (can % primes.at(k) == 0)
+                good = false;
+        }
+        if (good)
+            primes.push_back(can); 
+    }
+}
+
+
+
+void append_ltp(int target_size) {
+    if (target_size <= ltp.size() + recent_ltp.size() ) {
+        ltp.insert( ltp.end(), recent_ltp.begin(), recent_ltp.end() );
+        return;
+    }
+    for (int d = 1; d <= 9; d++) {
+        for (int r = 0; r < recent_ltp.size(); r++ ) {
+            char str[20];
+            int num = recent_ltp.at(r);
+            sprintf(str, "%d%d", d, num);
+            int new_num = atoi(str);
+            if (is_prime(new_num)) 
+                new_ltp.push_back(new_num);
+        }
+    }
+    ltp.insert( ltp.end(), recent_ltp.begin(), recent_ltp.end() );
+    recent_ltp = new_ltp;
+    new_ltp = {};
+    append_ltp(target_size);
+}
+
+
+
+int main() {
+    append_primes(1000);
+    append_ltp(20);
+    for (int i = 0; i < 20; i++) {
+        cout << ltp.at(i) << endl;
+    }
+    return 0;
+}
diff --git a/challenge-147/cheok-yin-fung/node/ch-1.js b/challenge-147/cheok-yin-fung/node/ch-1.js
new file mode 100644
index 0000000000..c3a75a954d
--- /dev/null
+++ b/challenge-147/cheok-yin-fung/node/ch-1.js
@@ -0,0 +1,60 @@
+// The Weekly Challenge 147
+// Task 1 Truncatable Prime
+// Friday, January 14, 2022 PM07:31:14 HKT
+
+let ltp = new Array();
+let recent_ltp = new Array(2,3,5,7);
+let new_ltp = new Array();
+
+let prime = new Array(2,3,5,7);
+
+
+
+function is_prime(t) {
+    for (let k = 0; prime[k] <= Math.sqrt(t); k++) {
+        if (t % prime[k] == 0)
+            return false;
+    }
+    return true;
+}
+
+
+
+function append_primes(max) {
+    HERE: for (can = prime[prime.length-1]+1; can <= max ; can++) {
+        for (let k=0; prime[k] <= Math.sqrt(can) ;k++) {
+            if (can % prime[k] == 0) {
+                continue HERE;
+            }
+        } 
+        prime.push(can);
+    }
+
+}
+
+
+
+function append_ltp(target_size) {
+    if (target_size <= ltp.length + recent_ltp.length) {
+        ltp = ltp.concat(recent_ltp);
+        return;
+    }
+    for (d = 1; d<=9; d++) {
+        for (num of recent_ltp) {
+            new_num = parseInt(d + '' + num);
+            if (is_prime(new_num)) {
+                new_ltp.push(new_num);
+            }
+        }
+    }
+    ltp = ltp.concat(recent_ltp);
+    recent_ltp = new_ltp;
+    new_ltp = new Array();
+    append_ltp(target_size);
+}
+
+
+
+append_primes(1000);
+append_ltp(20);
+console.log(ltp.slice(0, 20));
diff --git a/challenge-147/cheok-yin-fung/perl/ch-1.pl b/challenge-147/cheok-yin-fung/perl/ch-1.pl
index 4fa2d26e7b..02212489b5 100644
--- a/challenge-147/cheok-yin-fung/perl/ch-1.pl
+++ b/challenge-147/cheok-yin-fung/perl/ch-1.pl
@@ -1,7 +1,7 @@
 # The Weekly Challenge 147
 # Task 1 Truncatable Prime
 # version 0: Thursday, January 13, 2022 PM04:18:51 HKT
-# version 1: Friday, January 14, 2022 AM01:20:32 
+# version 1: Friday, January 14, 2022 PM12:34 HKT
 
 use v5.12.0;
 use warnings;
@@ -18,7 +18,7 @@ my @prime = (2,3,5,7);
 
 sub is_prime {
     my $t = $_[0];
-    for (my $k = 0; $prime[$k] <= sqrt($t) ;$k++) {
+    for (my $k = 0; $prime[$k] <= sqrt($t); $k++) {
         return 0 if $t % $prime[$k] == 0;
     } 
     return 1;
@@ -26,13 +26,12 @@ sub is_prime {
 
 
 
-sub append_arr_of_primes {
+sub append_primes {
     my $max = $_[0];
-    my $sqrtmax = sqrt($max);
-    my @relatively_small_primes = grep { $_ <= $sqrtmax } @prime;
-    HERE: for my $can ($relatively_small_primes[-1]+1..$max) {
-        for my $p (@relatively_small_primes) {
-            next HERE if $can % $p == 0
+    HERE: for my $can ($prime[-1]+1..$max) {
+        for my $p (@prime) {
+            next HERE if $can % $p == 0;
+            last if $p > sqrt($can);
         }
         push @prime, $can;
     }
@@ -40,7 +39,7 @@ sub append_arr_of_primes {
 
 
 
-sub append_arr_of_ltp {
+sub append_ltp {
     my $target_size = $_[0];
     if ($target_size <= (scalar @ltp + scalar @recent_ltp)) {
         push @ltp, @recent_ltp;
@@ -55,12 +54,12 @@ sub append_arr_of_ltp {
     push @ltp, @recent_ltp;
     @recent_ltp = @new_ltp;
     @new_ltp = ();
-    append_arr_of_ltp($target_size);
+    append_ltp($target_size);
 }
 
 
 
-append_arr_of_primes(1000);
-append_arr_of_ltp(20);
+append_primes(1000);
+append_ltp(20);
 say $_ for @ltp[0..19];