1070 Mooncake (25 minutos)

1. Tema

2. Ideas

1. En primer lugar ordenadas por Precio
2. En conformidad con los requisitos

3. Toma nota

La demanda y el inventario son dobles y no necesariamente int

4. Código

#include<cstdio>
#include<algorithm>
#include<string>
#include<vector>
#include<set>
#include<iostream> 

// 20:46 - 21:18
using namespace std;

bool cmp(pair<int, double> a, pair<int, double> b){
    return a.second > b.second;
}

int main(){
    int n;
    double all;
    double sum = 0;
    vector<double> counts;
    vector<double> price;
    vector<pair<int, double> > preprice; 
    scanf("%d %lf", &n, &all);
    for(int i=0;i<n;i++){
        double count;
        scanf("%lf", &count);
        counts.push_back(count);
    }
    for(int i=0;i<n;i++){
        double p;
        scanf("%lf", &p);
        price.push_back(p);
        preprice.push_back(make_pair(i, p/counts[i]));
    }
    sort(preprice.begin(), preprice.end(), cmp);
    for(int i=0;i<preprice.size();i++){
        if(all >= counts[preprice[i].first]){
            sum += price[preprice[i].first];
            all -= counts[preprice[i].first];
        }else if(all == 0){
            break;
        }else{
            sum += (all/counts[preprice[i].first])*price[preprice[i].first];
            all = 0;
            break;
        }
    }
    printf("%.2f", sum);
}