题解 | #百钱买百鸡问题#

#include <iostream>
using namespace std;




int main() {
    int a;
    cin >> a;
    for(int x = 0; x <= 14; x++){
        if((100 - 7*x) % 4 == 0){
            int y = (100-7*x)/4;
            int z = 100 - x - y;
            cout << x <<" " << y << " " << z << endl;
        }
    }

}

解方程思想

5x + 3y + z/3 = 100

x + y + z = 100

可以得到,

y=(100-7x)/4,由此得到x的取值范围去遍历

z=100-x-y