sgu 276

#include <stdio.h>


int main() {
    int p, s;
    int t[] = {1, 300, 900, 1800, 10800 };
    scanf("%d%d", &s, &p);


    p -= s;
    s = 0;
    while (t[s] <= p) ++s;


    printf("%d\n", s);


    return 0;
}