#include <stdio.h>
#include <string.h>
#include <stdlib.h>

void hex2raw(char* out, char* in, int len) {
  int i = 0;
  char* idx = in;
  char next[3]; next[2] = '\0';
  while(*idx != '\0' && i < len - 1) {
   strncpy(next, idx, 2);
   sscanf(next, "%hhx", &(out[i++]));
   idx += 2;
  }
  out[i] = '\0';
}

int main(int argc, char** argv) {
  char pattern[32];
  char script[1024];
  char buffer[2048];

  if (argc < 4) {
   printf("Usage: %s pad_pattern pad_len script\n", argv[0]);
   return 2;
  }

  hex2raw(pattern, argv[1], sizeof pattern);
  hex2raw(script, argv[3], sizeof script);

  int len = atoi(argv[2]);

  if (strlen(pattern) * len + strlen(script) >= 2000) {
    printf("Input too long.\n");
    return 1;
  }

  for (int i=0; i<len; i++)
  {
    printf("%s", pattern);
  }

  printf("%s\n", script);
}