Add Basic, C and C++ solutions to challenge 102

6 files changed, 355 insertions, 0 deletions

diff --git a/challenge-102/paulo-custodio/basic/ch-1.bas b/challenge-102/paulo-custodio/basic/ch-1.bas
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+' Challenge 102
+' 
+' TASK #1 > Rare Numbers
+' Submitted by: Mohammad S Anwar
+' 
+' You are given a positive integer $N.
+' 
+' Write a script to generate all Rare numbers of size $N if exists. Please 
+' checkout the page for more information about it.
+' Examples
+' 
+' (a) 2 digits: 65
+' (b) 6 digits: 621770
+' (c) 9 digits: 281089082
+
+' convert 1234 to 4321
+function invert_number(a as Integer) as Integer
+	dim a1 as Integer
+	do while a<>0
+		a1 = a1*10 + (a mod 10)
+		a = int(a / 10)
+	loop
+	invert_number = a1
+end function
+
+' check if number is a perfect square
+function is_perfect_square(n as Integer) as Boolean
+	dim sq as Double
+	sq = sqr(CDbl(n))
+	if int(sq)^2=n then
+		is_perfect_square = True
+	else
+		is_perfect_square = False
+	end if
+end function	
+
+' print all rare numbers with n digits
+sub print_rare_numbers(n as Integer)
+	dim r as Integer, r1 as Integer
+	for r=10^(n-1) to 10^(n)-1
+		r1 = invert_number(r)
+		if is_perfect_square(r+r1) then
+			if r>=r1 then
+				if is_perfect_square(r-r1) then
+					print trim(str(r))
+				end if
+			end if
+		end if
+	next
+end sub
+
+' main
+print_rare_numbers val(Command(1))
diff --git a/challenge-102/paulo-custodio/basic/ch-2.bas b/challenge-102/paulo-custodio/basic/ch-2.bas
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+' Challenge 102
+' 
+' TASK #2 › Hash-counting String
+' Submitted by: Stuart Little
+' 
+' You are given a positive integer $N.
+' 
+' Write a script to produce Hash-counting string of that length.
+' 
+' The definition of a hash-counting string is as follows:
+' - the string consists only of digits 0-9 and hashes, ‘#’
+' - there are no two consecutive hashes: ‘##’ does not appear in your string
+' - the last character is a hash
+' - the number immediately preceding each hash (if it exists) is the position 
+' of that hash in the string, with the position being counted up from 1
+' 
+' It can be shown that for every positive integer N there is exactly one such 
+' length-N string.
+' Examples:
+' 
+' (a) "#" is the counting string of length 1
+' (b) "2#" is the counting string of length 2
+' (c) "#3#" is the string of length 3
+' (d) "#3#5#7#10#" is the string of length 10
+' (e) "2#4#6#8#11#14#" is the string of length 14
+
+function hash_count(n as Integer) as String
+	Dim res as String, i as Integer, p as Integer
+	i = n
+	do while i>0
+		p = i
+		res = "#" & res
+		i = i-1
+		do while i>0 and p<>0
+			res = chr(asc("0") + (p mod 10)) & res
+			p = int(p / 10)
+			i = i-1
+		loop
+	loop
+	hash_count = res
+end function
+
+'main
+print hash_count(val(Command(1)))
diff --git a/challenge-102/paulo-custodio/c/ch-1.c b/challenge-102/paulo-custodio/c/ch-1.c
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+++ b/challenge-102/paulo-custodio/c/ch-1.c
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+/*
+Challenge 102
+
+TASK #1 › Rare Numbers
+Submitted by: Mohammad S Anwar
+
+You are given a positive integer $N.
+
+Write a script to generate all Rare numbers of size $N if exists. Please
+checkout the page for more information about it.
+Examples
+
+(a) 2 digits: 65
+(b) 6 digits: 621770
+(c) 9 digits: 281089082
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <math.h>
+
+int ipow(int base, int exp) {
+    int result = 1;
+    for (;;) {
+        if (exp & 1)
+            result *= base;
+        exp >>= 1;
+        if (!exp)
+            break;
+        base *= base;
+    }
+    return result;
+}
+
+int invert_number(int r) {
+    int r1 = 0;
+    while (r != 0) {
+        r1 = r1 * 10 + (r % 10);
+        r = r / 10;
+    }
+    return r1;
+}
+
+bool is_perfect_square(int n) {
+    double s = sqrt((double)n);
+    if (floor(s) == s)
+        return true;
+    else
+        return false;
+}
+
+void print_rare(int n) {
+    int start = ipow(10, n - 1);
+    int end = ipow(10, n );
+    for (int r = start; r < end; r++) {
+        int r1 = invert_number(r);
+        if (is_perfect_square(r + r1) && r >= r1 && is_perfect_square(r - r1))
+            printf("%d\n", r);
+    }
+}
+
+int main(int argc, char* argv[]) {
+    if (argc != 2) {
+        fputs("Usage: ch-1 N\n", stderr);
+        return EXIT_FAILURE;
+    }
+    else
+        print_rare(atoi(argv[1]));
+}
diff --git a/challenge-102/paulo-custodio/c/ch-2.c b/challenge-102/paulo-custodio/c/ch-2.c
new file mode 100644
index 0000000000..c0e1b06f06
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+++ b/challenge-102/paulo-custodio/c/ch-2.c
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+/*
+Challenge 102
+
+TASK #2 › Hash-counting String
+Submitted by: Stuart Little
+
+You are given a positive integer $N.
+
+Write a script to produce Hash-counting string of that length.
+
+The definition of a hash-counting string is as follows:
+- the string consists only of digits 0-9 and hashes, ‘#’
+- there are no two consecutive hashes: ‘##’ does not appear in your string
+- the last character is a hash
+- the number immediately preceding each hash (if it exists) is the position
+of that hash in the string, with the position being counted up from 1
+
+It can be shown that for every positive integer N there is exactly one such
+length-N string.
+Examples:
+
+(a) "#" is the counting string of length 1
+(b) "2#" is the counting string of length 2
+(c) "#3#" is the string of length 3
+(d) "#3#5#7#10#" is the string of length 10
+(e) "2#4#6#8#11#14#" is the string of length 14
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+void* check_mem(void* p) {
+    if (!p) {
+        fputs("Out of memory", stderr);
+        exit(EXIT_FAILURE);
+    }
+    return p;
+}
+
+char* hash_count(int n) {
+    char* str = check_mem(malloc(n + 1));
+    str[n] = '\0';
+    int i = n - 1;
+    while (i >= 0) {
+        int pos = i + 1;
+        str[i--] = '#';
+        while (i >= 0 && pos != 0) {
+            str[i--] = '0' + (pos % 10);
+            pos /= 10;
+        }
+    }
+    return str;
+}
+
+
+int main(int argc, char* argv[]) {
+    if (argc != 2) {
+        fputs("Usage: ch-1 N\n", stderr);
+        return EXIT_FAILURE;
+    }
+    else {
+        char* str = hash_count(atoi(argv[1]));
+        printf("%s\n", str);
+        free(str);
+    }
+}
diff --git a/challenge-102/paulo-custodio/cpp/ch-1.cpp b/challenge-102/paulo-custodio/cpp/ch-1.cpp
new file mode 100644
index 0000000000..01d88ccd5a
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@@ -0,0 +1,68 @@
+/*
+Challenge 102
+
+TASK #1 › Rare Numbers
+Submitted by: Mohammad S Anwar
+
+You are given a positive integer $N.
+
+Write a script to generate all Rare numbers of size $N if exists. Please
+checkout the page for more information about it.
+Examples
+
+(a) 2 digits: 65
+(b) 6 digits: 621770
+(c) 9 digits: 281089082
+*/
+
+#include <iostream>
+#include <cmath>
+
+int ipow(int base, int exp) {
+    int result = 1;
+    for (;;) {
+        if (exp & 1)
+            result *= base;
+        exp >>= 1;
+        if (!exp)
+            break;
+        base *= base;
+    }
+    return result;
+}
+
+int invert_number(int r) {
+    int r1 = 0;
+    while (r != 0) {
+        r1 = r1 * 10 + (r % 10);
+        r = r / 10;
+    }
+    return r1;
+}
+
+bool is_perfect_square(int n) {
+    double s = sqrt((double)n);
+    if (floor(s) == s)
+        return true;
+    else
+        return false;
+}
+
+void print_rare(int n) {
+    int start = ipow(10, n - 1);
+    int end = ipow(10, n );
+    for (int r = start; r < end; r++) {
+        int r1 = invert_number(r);
+        if (is_perfect_square(r + r1) && r >= r1 && is_perfect_square(r - r1))
+            std::cout << r << std::endl;
+    }
+}
+
+int main(int argc, char* argv[]) {
+    if (argc != 2) {
+        std::cerr << "Usage: ch-1 N" << std::endl;
+        return EXIT_FAILURE;
+    }
+    else
+        print_rare(atoi(argv[1]));
+}
diff --git a/challenge-102/paulo-custodio/cpp/ch-2.cpp b/challenge-102/paulo-custodio/cpp/ch-2.cpp
new file mode 100644
index 0000000000..24fbf2fb06
--- /dev/null
+++ b/challenge-102/paulo-custodio/cpp/ch-2.cpp
@@ -0,0 +1,54 @@
+/*
+Challenge 102
+
+TASK #2 › Hash-counting String
+Submitted by: Stuart Little
+
+You are given a positive integer $N.
+
+Write a script to produce Hash-counting string of that length.
+
+The definition of a hash-counting string is as follows:
+- the string consists only of digits 0-9 and hashes, ‘#’
+- there are no two consecutive hashes: ‘##’ does not appear in your string
+- the last character is a hash
+- the number immediately preceding each hash (if it exists) is the position
+of that hash in the string, with the position being counted up from 1
+
+It can be shown that for every positive integer N there is exactly one such
+length-N string.
+Examples:
+
+(a) "#" is the counting string of length 1
+(b) "2#" is the counting string of length 2
+(c) "#3#" is the string of length 3
+(d) "#3#5#7#10#" is the string of length 10
+(e) "2#4#6#8#11#14#" is the string of length 14
+*/
+
+#include <iostream>
+#include <string>
+
+std::string hash_count(int n) {
+    std::string str(n, ' ');
+    int i = n - 1;
+    while (i >= 0) {
+        int pos = i + 1;
+        str[i--] = '#';
+        while (i >= 0 && pos != 0) {
+            str[i--] = '0' + (pos % 10);
+            pos /= 10;
+        }
+    }
+    return str;
+}
+
+
+int main(int argc, char* argv[]) {
+    if (argc != 2) {
+        std::cerr << "Usage: ch-1 N" << std::endl;
+        return EXIT_FAILURE;
+    }
+    else 
+        std::cout << hash_count(atoi(argv[1])) << std::endl;
+}