题解 | 计算商品打折结算金额

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    double price;
    cin >> price;
    double cost = 0.00;
    if (price>=100){
        if(price>=500){
            if(price>=2000){
                if(price>=5000){
                    cost=price*0.60;
                }
                else{cost=price*0.70;}
            }
            else{cost=price*0.80;}
        }
        else{cost=price*0.90;}
    }
    else{cost=price;}

    cout << setiosflags(ios::fixed) << setprecision(1) << cost << endl;

    return 0;
}