#include <stdio.h>

int main() {
    int m = 0;
    int t = 0;
    int s = 0;

    scanf("%d%d%d", &m, &t, &s);

    if (t == 0) {
        printf("%d", m);
    } else {
        int remaining = (s % t == 0) ? (m - s / t) : (m - s / t - 1);
        printf("%d", (remaining < 0) ? 0 : remaining);
    }

    return 0;
}