#include <stdio.h>
#define FILENAME "largest.dat"

int main () {
  FILE *data;
  int largest, x, res;

  data = fopen(FILENAME, "r");
  /* should check for data == NULL */

  fscanf(data, "%i", &largest);

  while ( !feof (data) ) {
    res = fscanf(data, "%i", &x);
  
    if ( res == 1 && x > largest ) {
      largest = x;
    }
  }
  fclose(data);

  printf("%i\n", largest);

  return 0;
}