Question

i need this program to also print out the number of combinations

#include <stdio.h>
#include <string.h>
#define N 10

void generate(char *array, int n)
{
   if (n==0)
   {
       printf("%s\n",array);
       return;
   }
   for (int i = 0; i < n; ++i)
   {
       // generate all of the permutations that end with the last element
       generate(array, n-1);
       // swap the element
       char temp = array[n-1];
       array[n-1] = array[(n%2)*i];
       array[(n%2)*i] = temp;
   }
}

int main(int argc, char const *argv[])
{
   char array[N];
   printf("Enter word: ");
   scanf("%s",array);
   generate(array, strlen(array));
   return 0;
}

Answer 1

#include <stdio.h>
#include <string.h>
#define N 10

void generate(char *array, int n, int* count)
{
   int i;
   if (n==0)
   {
       printf("%s\n",array);
       *count = *count + 1;
       return;
   }
   for (i = 0; i < n; ++i)
   {
       // generate all of the permutations that end with the last element
       generate(array, n-1, count);
       // swap the element
       char temp = array[n-1];
       array[n-1] = array[(n%2)*i];
       array[(n%2)*i] = temp;
   }
   
}

int main(int argc, char const *argv[])
{
   char array[N];
   int count = 0;
   printf("Enter word: ");
   scanf("%s",array);
   generate(array, strlen(array), &count);
   printf("Total number of combinations = %d\n",count);
   return 0;
}