题解

#include<iostream>
#include<cmath>
using namespace std;
int pencil;
double num1,cash1;
double num2,cash2;
double num3,cash3;
int box1,box2,box3;
int money;
int main(){
	cin>>pencil;
	cin>>num1>>cash1;
    cin>>num2>>cash2;
	cin>>num3>>cash3;
	box1=ceil(pencil/num1)*cash1;
	box2=ceil(pencil/num2)*cash2;
	box3=ceil(pencil/num3)*cash3;
	money=min(min(box1,box2),box3);
	cout<<money;
	return 0;
}