Add solution for problem 32 in C

C/p032.c

@@ -0,0 +1,129 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "projecteuler.h"
+
+int compare(void *a, void *b);
+
+int main(int argc, char **argv)
+{
+   int a, b, i, j, k, p, p1, d, sum, n=0;
+   int digits[10];
+   int **products;
+   double elapsed;
+   struct timespec start, end;
+
+   clock_gettime(CLOCK_MONOTONIC, &start);
+
+   if((products = (int **)malloc(100*sizeof(int *))) == NULL)
+   {
+      fprintf(stderr, "Error while allocating memory\n");
+      return 1;
+   }
+
+   for(i = 0; i < 100; i++)
+   {
+      if((products[i] = (int *)malloc(sizeof(int))) == NULL)
+      {
+         fprintf(stderr, "Error while allocating memory\n");
+         return 1;
+      }
+   }
+
+   for(i = 2; i <= 99; i++)
+   {
+      for(j = 100; j <= 9999; j++)
+      {
+         a = i;
+         b = j;
+         p = a * b;
+
+         for(k = 0; k < 10; k++)
+         {
+            digits[k] = 0;
+         }
+         
+         do
+         {
+            d = a % 10;
+            digits[d]++;
+            a /= 10;
+         }while(a > 0);
+
+         do
+         {
+            d = b % 10;
+            digits[d]++;
+            b /= 10;
+         }while(b > 0);
+
+         p1 = p;
+
+         do
+         {
+            d = p1 % 10;
+            digits[d]++;
+            p1 /= 10;
+         }while(p1 > 0);
+
+         k = 0;
+
+         if(digits[0] == 0)
+         {
+            for(k = 1; k < 10; k++)
+            {
+               if(digits[k] > 1 || digits[k] == 0)
+               {
+                  break;
+               }
+            }
+         }
+
+         if(k == 10)
+         {
+            *products[n] = p;
+            n++;
+         }
+      }
+   }
+
+   quick_sort((void **)products, 0, 99, compare);
+
+   sum = *products[0];
+
+   for(i = 1; i < 100; i++)
+   {
+      if(*products[i] != *products[i-1])
+      {
+         sum += *products[i];
+      }
+   }
+
+   for(i = 0; i < 100; i++)
+   {
+      free(products[i]);
+   }
+
+   free(products);
+
+   clock_gettime(CLOCK_MONOTONIC, &end);
+
+   elapsed = (end.tv_sec - start.tv_sec) + (double)(end.tv_nsec - start.tv_nsec) / 1000000000;
+
+   printf("Project Euler, Problem 32\n");
+   printf("Answer: %d\n", sum);
+
+   printf("Elapsed time: %.9lf seconds\n", elapsed);
+
+   return 0;
+}
+
+int compare(void *a, void *b)
+{
+   int *n1, *n2;
+
+   n1 = (int *)a;
+   n2 = (int *)b;
+
+   return *n1 - *n2;
+}