#include <stdio.h>

int main()
{
    int n = 0;  //总共n盒酸奶
    int h = 0;  //喝完一盒酸奶的时间
    int m = 0;  //经过m分钟
    //多组输入
    while (~scanf("%d %d %d", &n, &h, &m))
    {
        if (m % h)
        {
            printf("%d\n", n - m / h - 1);
        }
        else
        {
            printf("%d\n", n - m / h);
        }
    }

    return 0;
}