#include <stdio.h>

void dumpletters (const unsigned int length, char *letters, unsigned int numletters) {
  char *output = new char[length];
  output[length] = 0;
  unsigned int i[] = new unsigned int[length];              // int (*a)[10];
  unsigned int level = 0;
  for(unsigned j=0; j<length; ++j) {
    i[j] = 0;
  }

  while(i[level] < numletters) {
    if(i[level] >= numletters) {
      --level;
      i[level] = 0;
    } else {
      output[level]=letters[ i[level] ];

      if(level >= length) {
        printf("%s\n",output);
      }

      ++level;
      ++i[level];
    }
  }
  delete output[];
  delete i[];
}

int main(int argc, char *argv[])
{
  char letters[]={'a','b','c'};
  dumpletters(2,letters,3);
  return 0;
}