技術標籤：HDU演算法

題目連結

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

struct MyStruct1
{
    int j, f; //JavaBean 、 貓糧 
    double value; //綜合價值
}Trade[1005];
//價值降序排序
bool cmp(MyStruct1 m1,MyStruct1 m2)
{
    return m1.value > m2.value;
}

int main()
{
    int
 
 m, n;
    double mao,sum;
    while (cin>>m>>n && m!=-1&&n!=-1)
    {
        for (int i = 0; i < n; i++)
        {
            cin >> Trade[i].j >> Trade[i].f;
            Trade[i].value = (1.0*Trade[i].j / Trade[i].f);
        }
        sort(Trade,Trade+n,cmp)
 
;
        mao = 0.0;//已經換的貓糧數目
        sum = 0.0;//換到的Java豆
        for (int i = 0; i < n; i++)
        {
            if (mao<=m)
            {
                if (mao + Trade[i].f <= m)
                {
                    mao += Trade[i].f;
                    sum += Trade[i].j;
                }
 

                else
                {
                    sum += (m - mao)*Trade[i].value;
                    mao = m;
                }
            }
            else
            {
                break;
            }
        }
        cout << setprecision(3) << fixed<<sum << endl;

    }
    return 0;
}