#include <iostream>
#include <algorithm>
#include <string>
#include <cmath>
#include <stack>
#include <vector>
#include <map>
#define REP(i,a) for(int i = 0; i < (a); i++)
using namespace std;

int main(){
	int n,m;
	cin >> n >> m;
	cout << n - m << endl;
}