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备注:
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#include <iostream>
#include <cstdio>
#include <iomanip>
#include <cmath>
#include <math.h>
#include <algorithm>
#include <cstring>
#include <string>
#include <stack>
#include <queue>
#include <algorithm>
#define LL long long
using namespace std;
const int INF = 0x3f3f3f3f;
const int N = 1e5 + 10;
int m , t , s , n , a;
int main()
{
	cin >> m >> t >> s;
	if(t == 0)
    {
    	cout << 0;
    	return 0;
    }
	a = s / t;
	n = m - a;
	cout << n;
	return 0;
}