Найти произведение чисел из файла, меньших заданного числа b.

#include <iostream>
#include <fstream>
 
using namespace std;
 
int main()
{
    const char* filename = "input.txt";
    ifstream ifs(filename, ifstream::in);
 
    int bound = -1;
    printf("b = "); scanf("%d",&bound);
 
    int mul = 1, value = 0;
    while ((ifs.peek() >= 0) && (ifs>>value))
     { if (value >= bound) break; mul*=value; }
 
    printf("mul = %d\n",mul);
}

int main()
{
    FILE* fp = NULL;
    const char* filename = "input.txt";
    if ((fp = fopen(filename,"r")) == NULL)
        printf("Unable to open file %s\n",filename);
 
    int bound = -1;
    printf("b = "); scanf("%d",&bound);
 
    int mul = 1, value = 0;
    while ((!feof(fp)) && (fscanf("%d",&value)))
     { if (value >= bound) break; mul*=value; }
 
    printf("mul = %d\n",mul);
 
    fclose(fp);
}