白駿1712損益バランスポイント.cpp

#include <iostream>
using namespace std;
int main(){
    long long a,b,c;
    cin >> a >> b >> c;
    if(b >= c){
        cout << -1 << endl;
        return 0;
    }
    long long BreakEvenPoint = (int)(a / (c-b));
    cout << BreakEvenPoint + 1 << endl;
 

    return 0;
}

while(1){
	if(TotalPrice >= TotalIncome){
		BreakEvenPoint++;
	}else{
		break;
	}
	//cout << TotalPrice << " " << TotalIncome << endl;
	TotalPrice = a + b*BreakEvenPoint;
	TotalIncome = c*BreakEvenPoint;
}