#include<bits/stdc++.h>
using namespace std;

int main(){
	int x,y,n;
    cin>>x>>y>>n;
	printf("%.0f",n-(x+y)*0.9);
	return 0;
}
/**************************************************************
	Problem: 1597
	User: linmiaoling
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/