Merge pull request #7681 from pauloscustodio/master

Add Perl, C, C++ and Forth solutions

26 files changed, 1448 insertions, 0 deletions

diff --git a/challenge-203/paulo-custodio/Makefile b/challenge-203/paulo-custodio/Makefile
new file mode 100644
index 0000000000..c3c762d746
--- /dev/null
+++ b/challenge-203/paulo-custodio/Makefile
@@ -0,0 +1,2 @@
+all:
+	perl ../../challenge-001/paulo-custodio/test.pl
diff --git a/challenge-203/paulo-custodio/basic/ch-1.bas b/challenge-203/paulo-custodio/basic/ch-1.bas
new file mode 100644
index 0000000000..bea5244b33
--- /dev/null
+++ b/challenge-203/paulo-custodio/basic/ch-1.bas
@@ -0,0 +1,67 @@
+' Challenge 203
+'
+' Task 1: Special Quadruplets
+' Submitted by: Mohammad S Anwar
+'
+' You are given an array of integers.
+'
+' Write a script to find out the total special quadruplets for the given array.
+'
+' Special Quadruplets are such that satisfies the following 2 rules.
+' 1) nums[a] + nums[b] + nums[c] == nums[d]
+' 2) a < b < c < d
+'
+'
+' Example 1
+'
+' Input: @nums = (1,2,3,6)
+' Output: 1
+'
+' Since the only special quadruplets found is
+' $nums[0] + $nums[1] + $nums[2] == $nums[3].
+'
+' Example 2
+'
+' Input: @nums = (1,1,1,3,5)
+' Output: 4
+'
+' $nums[0] + $nums[1] + $nums[2] == $nums[3]
+' $nums[0] + $nums[1] + $nums[3] == $nums[4]
+' $nums[0] + $nums[2] + $nums[3] == $nums[4]
+' $nums[1] + $nums[2] + $nums[3] == $nums[4]
+'
+' Example 3
+'
+' Input: @nums = (3,3,6,4,5)
+' Output: 0
+
+function num_quadruplets(nums() as integer) as integer
+    dim count as integer, a as integer, b as integer, c as integer, d as integer
+    count=0
+    for a=0 to ubound(nums)-3
+        for b=a+1 to ubound(nums)-2
+            for c=b+1 to ubound(nums)-1
+                for d=c+1 to ubound(nums)
+                    if nums(a)+nums(b)+nums(c)=nums(d) then
+                        count=count+1
+                    end if
+                next
+            next
+        next
+    next
+    num_quadruplets=count
+end function
+
+sub collect_args(nums() as integer)
+    dim i as integer
+    i=0
+    do while command(i+1)<>""
+        redim preserve nums(i) as integer
+        nums(i)=val(command(i+1))
+        i=i+1
+    loop
+end sub
+
+dim nums() as integer
+collect_args nums()
+print num_quadruplets(nums())
diff --git a/challenge-203/paulo-custodio/basic/ch-2.bas b/challenge-203/paulo-custodio/basic/ch-2.bas
new file mode 100644
index 0000000000..9a5efeb27e
--- /dev/null
+++ b/challenge-203/paulo-custodio/basic/ch-2.bas
@@ -0,0 +1,82 @@
+' Challenge 203
+'
+' Task 2: Copy Directory
+' Submitted by: Julien Fiegehenn
+'
+' You are given path to two folders, $source and $target.
+'
+' Write a script that recursively copy the directory from $source to $target
+' except any files.
+'
+' Example
+'
+' Input: $source = '/a/b/c' and $target = '/x/y'
+'
+' Source directory structure:
+'
+' ├── a
+' │   └── b
+' │       └── c
+' │           ├── 1
+' │           │   └── 1.txt
+' │           ├── 2
+' │           │   └── 2.txt
+' │           ├── 3
+' │           │   └── 3.txt
+' │           ├── 4
+' │           └── 5
+' │               └── 5.txt
+'
+' Target directory structure:
+'
+' ├── x
+' │   └── y
+'
+' Expected Result:
+'
+' ├── x
+' │   └── y
+' |       ├── 1
+' │       ├── 2
+' │       ├── 3
+' │       ├── 4
+' │       └── 5
+
+# include "dir.bi"
+
+sub get_dirs(path as string, dirs() as string)
+    dim i as integer, d as string
+    i=0
+    d=dir(path & "/*", fbDirectory)
+    do while d<>""
+        if d<>"." and d<>".." then
+            redim preserve dirs(i) as string
+            dirs(i)=d
+            i=i+1
+        end if
+        d=dir()
+    loop
+end sub
+
+sub make_path(path as string)
+    dim p as integer
+    p=0
+    do
+        p=instr(p+1, path, "/")
+        if p=0 then exit do
+        mkdir left(path,p-1)
+    loop
+    mkdir path
+end sub
+
+sub copy_dirs(source as string, target as string)
+    dim dirs() as string, i as integer
+
+    get_dirs source, dirs()
+    for i=0 to ubound(dirs)
+        make_path target & "/" & dirs(i)
+        copy_dirs source & "/" & dirs(i), target & "/" & dirs(i)
+    next
+end sub
+
+copy_dirs command(1), command(2)
diff --git a/challenge-203/paulo-custodio/c/ch-1.c b/challenge-203/paulo-custodio/c/ch-1.c
new file mode 100644
index 0000000000..d4926a7d1a
--- /dev/null
+++ b/challenge-203/paulo-custodio/c/ch-1.c
@@ -0,0 +1,61 @@
+/*
+Challenge 203
+
+Task 1: Special Quadruplets
+Submitted by: Mohammad S Anwar
+
+You are given an array of integers.
+
+Write a script to find out the total special quadruplets for the given array.
+
+Special Quadruplets are such that satisfies the following 2 rules.
+1) nums[a] + nums[b] + nums[c] == nums[d]
+2) a < b < c < d
+
+
+Example 1
+
+Input: @nums = (1,2,3,6)
+Output: 1
+
+Since the only special quadruplets found is
+$nums[0] + $nums[1] + $nums[2] == $nums[3].
+
+Example 2
+
+Input: @nums = (1,1,1,3,5)
+Output: 4
+
+$nums[0] + $nums[1] + $nums[2] == $nums[3]
+$nums[0] + $nums[1] + $nums[3] == $nums[4]
+$nums[0] + $nums[2] + $nums[3] == $nums[4]
+$nums[1] + $nums[2] + $nums[3] == $nums[4]
+
+Example 3
+
+Input: @nums = (3,3,6,4,5)
+Output: 0
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int num_quadruplets(int nums[], int nums_size) {
+    int count = 0;
+    for (int a = 0; a < nums_size - 3; a++)
+        for (int b = a + 1; b < nums_size - 2; b++)
+            for (int c = b + 1; c < nums_size - 1; c++)
+                for (int d = c + 1; d < nums_size; d++)
+                    if (nums[a]+nums[b]+nums[c]==nums[d])
+                        count++;
+    return count;
+}
+
+int main(int argc, char* argv[]) {
+    argv++; argc--;
+    int* nums = malloc(argc*sizeof(int));
+    for (int i = 0; i < argc; i++)
+        nums[i] = atoi(argv[i]);
+    printf("%d\n", num_quadruplets(nums, argc));
+    free(nums);
+}
diff --git a/challenge-203/paulo-custodio/c/ch-2.c b/challenge-203/paulo-custodio/c/ch-2.c
new file mode 100644
index 0000000000..6a817bdbc2
--- /dev/null
+++ b/challenge-203/paulo-custodio/c/ch-2.c
@@ -0,0 +1,122 @@
+/*
+Challenge 203
+
+Task 2: Copy Directory
+Submitted by: Julien Fiegehenn
+
+You are given path to two folders, $source and $target.
+
+Write a script that recursively copy the directory from $source to $target
+except any files.
+
+Example
+
+Input: $source = '/a/b/c' and $target = '/x/y'
+
+Source directory structure:
+
+├── a
+│   └── b
+│       └── c
+│           ├── 1
+│           │   └── 1.txt
+│           ├── 2
+│           │   └── 2.txt
+│           ├── 3
+│           │   └── 3.txt
+│           ├── 4
+│           └── 5
+│               └── 5.txt
+
+Target directory structure:
+
+├── x
+│   └── y
+
+Expected Result:
+
+├── x
+│   └── y
+|       ├── 1
+│       ├── 2
+│       ├── 3
+│       ├── 4
+│       └── 5
+*/
+
+#define MAX_PATH    1024
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+
+const char* cat_path(const char* dir, const char* file) {
+    static char path[MAX_PATH];
+    assert(strlen(dir)+1+strlen(file)+1 < MAX_PATH);
+
+    strcpy(path, dir);
+    strcat(path, "/");
+    strcat(path, file);
+    return path;
+}
+
+void os_mkdir(const char* path) {
+#ifdef _WIN32
+    mkdir(path);
+#else
+    mkdir(path, 0777);
+#endif
+}
+
+void make_path(const char* path) {
+    char dir[MAX_PATH];
+    const char* p = path;
+    const char* p0 = p;
+
+    while ((p = strchr(p0, '/')) != NULL) {
+        strcpy(dir, path);
+        dir[p-path] = '\0';
+
+        os_mkdir(dir);
+        p0 = p + 1;
+    }
+    os_mkdir(path);
+}
+
+void copy_dirs(const char* source, const char* target) {
+    DIR *dp;
+    struct dirent *ep;
+    dp = opendir(source);
+    if (dp != NULL) {
+        while ((ep = readdir(dp)) != NULL)  {
+            if (strcmp(ep->d_name, ".") != 0 && strcmp(ep->d_name, "..") != 0) {
+                char source_file[MAX_PATH];
+                strcpy(source_file, cat_path(source, ep->d_name));
+
+                struct stat statbuf;
+                if (stat(source_file, &statbuf) == 0) {
+                    if ((statbuf.st_mode & S_IFMT) == S_IFDIR) {
+                        char target_file[MAX_PATH];
+                        strcpy(target_file, cat_path(target, ep->d_name));
+
+                        make_path(target_file);
+                        copy_dirs(source_file, target_file);
+                    }
+                }
+            }
+        }
+        closedir(dp);
+    }
+}
+
+int main(int argc, char* argv[]) {
+    argv++; argc--;
+    if (argc != 2)
+        fputs("usage: ch-1 source target", stderr);
+    else {
+        copy_dirs(argv[0], argv[1]);
+    }
+}
diff --git a/challenge-203/paulo-custodio/cpp/ch-1.cpp b/challenge-203/paulo-custodio/cpp/ch-1.cpp
new file mode 100644
index 0000000000..d49c659de7
--- /dev/null
+++ b/challenge-203/paulo-custodio/cpp/ch-1.cpp
@@ -0,0 +1,61 @@
+/*
+Challenge 203
+
+Task 1: Special Quadruplets
+Submitted by: Mohammad S Anwar
+
+You are given an array of integers.
+
+Write a script to find out the total special quadruplets for the given array.
+
+Special Quadruplets are such that satisfies the following 2 rules.
+1) nums[a] + nums[b] + nums[c] == nums[d]
+2) a < b < c < d
+
+
+Example 1
+
+Input: @nums = (1,2,3,6)
+Output: 1
+
+Since the only special quadruplets found is
+$nums[0] + $nums[1] + $nums[2] == $nums[3].
+
+Example 2
+
+Input: @nums = (1,1,1,3,5)
+Output: 4
+
+$nums[0] + $nums[1] + $nums[2] == $nums[3]
+$nums[0] + $nums[1] + $nums[3] == $nums[4]
+$nums[0] + $nums[2] + $nums[3] == $nums[4]
+$nums[1] + $nums[2] + $nums[3] == $nums[4]
+
+Example 3
+
+Input: @nums = (3,3,6,4,5)
+Output: 0
+*/
+
+#include <iostream>
+#include <vector>
+
+int num_quadruplets(const std::vector<int>& nums) {
+    int count = 0;
+    if (nums.size() >= 4)
+        for (size_t a = 0; a < nums.size() - 3; a++)
+            for (size_t b = a + 1; b < nums.size() - 2; b++)
+                for (size_t c = b + 1; c < nums.size() - 1; c++)
+                    for (size_t d = c + 1; d < nums.size(); d++)
+                        if (nums[a]+nums[b]+nums[c]==nums[d])
+                            count++;
+    return count;
+}
+
+int main(int argc, char* argv[]) {
+    argv++; argc--;
+    std::vector<int> nums;
+    for (int i = 0; i < argc; i++)
+        nums.push_back(atoi(argv[i]));
+    std:: cout << num_quadruplets(nums) << std::endl;
+}
diff --git a/challenge-203/paulo-custodio/cpp/ch-2.cpp b/challenge-203/paulo-custodio/cpp/ch-2.cpp
new file mode 100644
index 0000000000..bef55b3d0d
--- /dev/null
+++ b/challenge-203/paulo-custodio/cpp/ch-2.cpp
@@ -0,0 +1,69 @@
+/*
+Challenge 203
+
+Task 2: Copy Directory
+Submitted by: Julien Fiegehenn
+
+You are given path to two folders, $source and $target.
+
+Write a script that recursively copy the directory from $source to $target
+except any files.
+
+Example
+
+Input: $source = '/a/b/c' and $target = '/x/y'
+
+Source directory structure:
+
+├── a
+│   └── b
+│       └── c
+│           ├── 1
+│           │   └── 1.txt
+│           ├── 2
+│           │   └── 2.txt
+│           ├── 3
+│           │   └── 3.txt
+│           ├── 4
+│           └── 5
+│               └── 5.txt
+
+Target directory structure:
+
+├── x
+│   └── y
+
+Expected Result:
+
+├── x
+│   └── y
+|       ├── 1
+│       ├── 2
+│       ├── 3
+│       ├── 4
+│       └── 5
+*/
+
+#include <iostream>
+#include <filesystem>
+
+namespace fs = std::filesystem;
+
+void copy_dirs(const fs::path& source, const fs::path& target) {
+    for (auto& dir_entry : fs::directory_iterator(source)) {
+        if (dir_entry.is_directory()) {
+            fs::path target_dir = target / dir_entry.path().filename();
+            fs::create_directories(target_dir);
+            copy_dirs(dir_entry, target_dir);
+        }
+    }
+}
+
+int main(int argc, char* argv[]) {
+    argv++; argc--;
+    if (argc != 2)
+        std::cerr << "usage: ch-1 source target" << std::endl;
+    else {
+        copy_dirs(fs::path(argv[0]), fs::path(argv[1]));
+    }
+}
diff --git a/challenge-203/paulo-custodio/forth/ch-1.fs b/challenge-203/paulo-custodio/forth/ch-1.fs
new file mode 100644
index 0000000000..1e91b0e685
--- /dev/null
+++ b/challenge-203/paulo-custodio/forth/ch-1.fs
@@ -0,0 +1,81 @@
+#! /usr/bin/env gforth
+
+\ Challenge 203
+\
+\ Task 1: Special Quadruplets
+\ Submitted by: Mohammad S Anwar
+\
+\ You are given an array of integers.
+\
+\ Write a script to find out the total special quadruplets for the given array.
+\
+\ Special Quadruplets are such that satisfies the following 2 rules.
+\ 1) nums[a] + nums[b] + nums[c] == nums[d]
+\ 2) a < b < c < d
+\
+\
+\ Example 1
+\
+\ Input: @nums = (1,2,3,6)
+\ Output: 1
+\
+\ Since the only special quadruplets found is
+\ $nums[0] + $nums[1] + $nums[2] == $nums[3].
+\
+\ Example 2
+\
+\ Input: @nums = (1,1,1,3,5)
+\ Output: 4
+\
+\ $nums[0] + $nums[1] + $nums[2] == $nums[3]
+\ $nums[0] + $nums[1] + $nums[3] == $nums[4]
+\ $nums[0] + $nums[2] + $nums[3] == $nums[4]
+\ $nums[1] + $nums[2] + $nums[3] == $nums[4]
+\
+\ Example 3
+\
+\ Input: @nums = (3,3,6,4,5)
+\ Output: 0
+
+CREATE nums 256 CELLS ALLOT
+0 VALUE nums_size
+
+: nums[] ( i -- addr )
+    CELLS nums +
+;
+
+: collect_args ( -- )
+    BEGIN NEXT-ARG DUP WHILE
+        0 0 2SWAP >NUMBER 2DROP DROP
+        nums_size nums[] !
+        nums_size 1+ TO nums_size
+    REPEAT
+    2DROP
+;
+
+: num_quadruplets ( -- n )
+    0 0 0 0 { a b c d }
+    0                       ( count )
+    0 TO a
+    BEGIN a nums_size 3 - < WHILE
+        a 1+ TO b
+        BEGIN b nums_size 2 - < WHILE
+            b 1+ TO c
+            BEGIN c nums_size 1- < WHILE
+                c 1+ TO d
+                BEGIN d nums_size < WHILE
+                    a nums[] @ b nums[] @ + c nums[] @ + d nums[] @ = IF
+                        1+
+                    THEN
+                    d 1+ to d
+                REPEAT
+                c 1+ TO c
+            REPEAT
+            b 1+ TO b
+        REPEAT
+        a 1+ TO a
+    REPEAT
+;
+
+collect_args num_quadruplets . CR
+BYE
diff --git a/challenge-203/paulo-custodio/forth/ch-2.fs b/challenge-203/paulo-custodio/forth/ch-2.fs
new file mode 100644
index 0000000000..d5a78799b1
--- /dev/null
+++ b/challenge-203/paulo-custodio/forth/ch-2.fs
@@ -0,0 +1,114 @@
+#! /usr/bin/env gforth
+
+\ Challenge 203
+\
+\ Task 2: Copy Directory
+\ Submitted by: Julien Fiegehenn
+\
+\ You are given path to two folders, $source and $target.
+\
+\ Write a script that recursively copy the directory from $source to $target
+\ except any files.
+\
+\ Example
+\
+\ Input: $source = '/a/b/c' and $target = '/x/y'
+\
+\ Source directory structure:
+\
+\ ├── a
+\ │   └── b
+\ │       └── c
+\ │           ├── 1
+\ │           │   └── 1.txt
+\ │           ├── 2
+\ │           │   └── 2.txt
+\ │           ├── 3
+\ │           │   └── 3.txt
+\ │           ├── 4
+\ │           └── 5
+\ │               └── 5.txt
+\
+\ Target directory structure:
+\
+\ ├── x
+\ │   └── y
+\
+\ Expected Result:
+\
+\ ├── x
+\ │   └── y
+\ |       ├── 1
+\ │       ├── 2
+\ │       ├── 3
+\ │       ├── 4
+\ │       └── 5
+
+\ copy text to counted string
+: copy_text { addr-from len addr-to -- }
+    addr-from addr-to 1+ len CMOVE
+    len addr-to C!
+;
+
+\ append text to counted string
+: cat_text { addr-cstr addr-from len-from -- }
+    addr-from  addr-cstr COUNT +  len-from  CMOVE
+    addr-cstr C@ len-from + addr-cstr C!
+;
+
+\ concat two paths
+: cat_paths { target addr-path1 len-path1 addr-path2 len-path2 -- }
+    0 target C!
+    target addr-path1 len-path1 cat_text
+    target S" /" cat_text
+    target addr-path2 len-path2 cat_text
+;
+
+: is_dot_dot_dot { cstr -- f }
+    cstr COUNT S" ." COMPARE 0=
+    cstr COUNT S" .." COMPARE 0= OR
+;
+
+: is_dir { cstr -- f }
+    cstr COUNT OPEN-DIR 0= IF \ ok
+        CLOSE-DIR THROW
+        TRUE
+    ELSE
+        DROP
+        FALSE
+    THEN
+;
+
+\ copy dirs
+: copy_dirs { source-addr target-addr -- }
+    source-addr COUNT OPEN-DIR THROW { dirid }
+    256 ALLOCATE THROW { fname }
+    BEGIN fname 1+ 255 dirid READ-DIR THROW WHILE
+        fname C!
+        fname is_dot_dot_dot 0= IF
+            256 ALLOCATE THROW { source-file }
+            source-file source-addr COUNT fname COUNT cat_paths
+
+            256 ALLOCATE THROW { target-file }
+            target-file target-addr COUNT fname COUNT cat_paths
+
+            source-file is_dir IF
+                target-file COUNT  [ 8 BASE ! 777 DECIMAL ] LITERAL
+                MKDIR-PARENTS THROW
+            THEN
+
+            source-file FREE THROW
+            target-file FREE THROW
+        THEN
+    REPEAT
+    fname FREE THROW
+;
+
+\ file names
+CREATE source_dir 256 ALLOT
+CREATE target_dir 256 ALLOT
+
+NEXT-ARG DUP 0= THROW source_dir copy_text
+NEXT-ARG DUP 0= THROW target_dir copy_text
+source_dir target_dir copy_dirs
+BYE
diff --git a/challenge-203/paulo-custodio/perl/ch-1.pl b/challenge-203/paulo-custodio/perl/ch-1.pl
new file mode 100644
index 0000000000..053b82ffde
--- /dev/null
+++ b/challenge-203/paulo-custodio/perl/ch-1.pl
@@ -0,0 +1,59 @@
+#!/usr/bin/perl
+
+# Challenge 203
+#
+# Task 1: Special Quadruplets
+# Submitted by: Mohammad S Anwar
+#
+# You are given an array of integers.
+#
+# Write a script to find out the total special quadruplets for the given array.
+#
+# Special Quadruplets are such that satisfies the following 2 rules.
+# 1) nums[a] + nums[b] + nums[c] == nums[d]
+# 2) a < b < c < d
+#
+#
+# Example 1
+#
+# Input: @nums = (1,2,3,6)
+# Output: 1
+#
+# Since the only special quadruplets found is
+# $nums[0] + $nums[1] + $nums[2] == $nums[3].
+#
+# Example 2
+#
+# Input: @nums = (1,1,1,3,5)
+# Output: 4
+#
+# $nums[0] + $nums[1] + $nums[2] == $nums[3]
+# $nums[0] + $nums[1] + $nums[3] == $nums[4]
+# $nums[0] + $nums[2] + $nums[3] == $nums[4]
+# $nums[1] + $nums[2] + $nums[3] == $nums[4]
+#
+# Example 3
+#
+# Input: @nums = (3,3,6,4,5)
+# Output: 0
+
+use Modern::Perl;
+
+sub num_quadruplets {
+    my(@nums) = @_;
+    my $count = 0;
+    for my $a (0..$#nums-3) {
+        for my $b ($a+1..$#nums-2) {
+            for my $c ($b+1..$#nums-1) {
+                for my $d ($c+1..$#nums) {
+                    if ($nums[$a]+$nums[$b]+$nums[$c]==$nums[$d]) {
+                        $count++;
+                    }
+                }
+            }
+        }
+    }
+    return $count;
+}
+
+say num_quadruplets(@ARGV);
diff --git a/challenge-203/paulo-custodio/perl/ch-2.pl b/challenge-203/paulo-custodio/perl/ch-2.pl
new file mode 100644
index 0000000000..7c6ae8e339
--- /dev/null
+++ b/challenge-203/paulo-custodio/perl/ch-2.pl
@@ -0,0 +1,63 @@
+#!/usr/bin/perl
+
+# Challenge 203
+#
+# Task 2: Copy Directory
+# Submitted by: Julien Fiegehenn
+#
+# You are given path to two folders, $source and $target.
+#
+# Write a script that recursively copy the directory from $source to $target
+# except any files.
+#
+# Example
+#
+# Input: $source = '/a/b/c' and $target = '/x/y'
+#
+# Source directory structure:
+#
+# ├── a
+# │   └── b
+# │       └── c
+# │           ├── 1
+# │           │   └── 1.txt
+# │           ├── 2
+# │           │   └── 2.txt
+# │           ├── 3
+# │           │   └── 3.txt
+# │           ├── 4
+# │           └── 5
+# │               └── 5.txt
+#
+# Target directory structure:
+#
+# ├── x
+# │   └── y
+#
+# Expected Result:
+#
+# ├── x
+# │   └── y
+# |       ├── 1
+# │       ├── 2
+# │       ├── 3
+# │       ├── 4
+# │       └── 5
+
+use Modern::Perl;
+use File::Find;
+use Path::Tiny;
+
+sub copy_dirs {
+    my($source, $target) = @_;
+    my @dirs;
+    find(sub {
+            return unless -d $_;
+            (my $path = $File::Find::name) =~ s/^$source/$target/;
+            push @dirs, $path;
+        }, $source);
+    path($_)->mkpath for @dirs;
+}
+
+@ARGV==2 or die "usage: ch-2.pl source target\n";
+copy_dirs(@ARGV);
diff --git a/challenge-203/paulo-custodio/t/test-1.yaml b/challenge-203/paulo-custodio/t/test-1.yaml
new file mode 100644
index 0000000000..ba74c95188
--- /dev/null
+++ b/challenge-203/paulo-custodio/t/test-1.yaml
@@ -0,0 +1,15 @@
+- setup:
+  cleanup:
+  args:     1 2 3 6
+  input:
+  output:   1
+- setup:
+  cleanup:
+  args:     1 1 1 3 5
+  input:
+  output:   4
+- setup:
+  cleanup:
+  args:     1 1 1 1
+  input:
+  output:   0
diff --git a/challenge-203/paulo-custodio/t/test-2.yaml b/challenge-203/paulo-custodio/t/test-2.yaml
new file mode 100644
index 0000000000..9db434b269
--- /dev/null
+++ b/challenge-203/paulo-custodio/t/test-2.yaml
@@ -0,0 +1,5 @@
+- setup:    0==system("mkdir -p a/b/c/1 a/b/c/2 a/b/c/3 a/b/c/4 a/b/c/5") && 0==system("touch a/b/c/1/1.txt a/b/c/2/2.txt a/b/c/3/3.txt a/b/c/5/5.txt")
+  cleanup:  -d "x/y/1" && -d "x/y/2" && -d "x/y/3" && -d "x/y/4" && -d "x/y/5" && ! -f "x/y/1/1.txt" && ! -f "x/y/2/2.txt" && ! -f "x/y/3/3.txt" && ! -f "x/y/5/5.txt" && 0==system("rm -rf a x")
+  args:     a/b/c x/y
+  input:
+  output:
diff --git a/challenge-207/paulo-custodio/Makefile b/challenge-207/paulo-custodio/Makefile
new file mode 100644
index 0000000000..c3c762d746
--- /dev/null
+++ b/challenge-207/paulo-custodio/Makefile
@@ -0,0 +1,2 @@
+all:
+	perl ../../challenge-001/paulo-custodio/test.pl
diff --git a/challenge-207/paulo-custodio/basic/ch-1.bas b/challenge-207/paulo-custodio/basic/ch-1.bas
new file mode 100644
index 0000000000..d5f8593713
--- /dev/null
+++ b/challenge-207/paulo-custodio/basic/ch-1.bas
@@ -0,0 +1,59 @@
+' Challenge 207
+'
+' Task 1: Keyboard Word
+' Submitted by: Mohammad S Anwar
+'
+' You are given an array of words.
+'
+' Write a script to print all the words in the given array that can be types
+' using alphabet on only one row of the keyboard.
+'
+' Let us assume the keys are arranged as below:
+'
+' Row 1: qwertyuiop
+' Row 2: asdfghjkl
+' Row 3: zxcvbnm
+'
+' Example 1
+'
+' Input: @words = ("Hello","Alaska","Dad","Peace")
+' Output: ("Alaska","Dad")
+'
+' Example 2
+'
+' Input: @array = ("OMG","Bye")
+' Output: ()
+
+function remove_char(byval s as string, c as string) as string
+    dim p as integer
+
+    p=instr(s,c)
+    do while p>0
+        s=left(s,p-1)+mid(s,p+1)
+        p=instr(s,c)
+    loop
+    remove_char=s
+end function
+
+function can_type_word(k as string, byval s as string) as boolean
+    dim i as integer
+    for i=1 to len(k)
+        s=remove_char(s,mid(k,i,1))
+    next
+    can_type_word=s=""
+end function
+
+function can_type(s as string) as boolean
+    s=lcase(s)
+    can_type=can_type_word("qwertyuiop",s) or _
+             can_type_word("asdfghjkl",s) or _
+             can_type_word("zxcvbnm",s)
+end function
+
+dim i as integer
+i=1
+do while command(i)<>""
+    if can_type(command(i)) then print command(i);" ";
+    i=i+1
+loop
+print
diff --git a/challenge-207/paulo-custodio/basic/ch-2.bas b/challenge-207/paulo-custodio/basic/ch-2.bas
new file mode 100644
index 0000000000..2e2dfae944
--- /dev/null
+++ b/challenge-207/paulo-custodio/basic/ch-2.bas
@@ -0,0 +1,70 @@
+' Challenge 207
+'
+' Task 2: H-Index
+' Submitted by: Mohammad S Anwar
+'
+' You are given an array of integers containing citations a researc