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

int main(void)
{
  int n;
  char *s;
  scanf("%d", &n);

  s = (char*)malloc(n*sizeof(char)+1);

  scanf("%s", s);

  while(s[2] != '\0') {
    char tmp;
    tmp = s[3];
    s[3] = '\0';
    if (strcmp("404", s) == 0) {
      printf("Found\n");
      return 0;
    }
    s[3] = tmp;
    s++;
  }

  printf("NotFound\n");
  return 0;
}