#include <iostream>
#include <math.h>
using namespace std;
int main()
{
		int h, t, count = 0 , base;
		cin >> h >> t;
		base = t;
		if (!(1 <= h && h >= 100) && (1 <= t && t >= 100)) return -1;
		else
		{
			while (h >= t) {
				t += base;
				count++;
			}
			cout << count;
		}
}