poj2709

模拟题，在合成灰色的时候，每次取当前剩余最多的三种颜色，各取1mL合成。然后重新看剩余最多的是哪三个。

#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <functional>
#include <queue>
using namespace std;
 
#define MAX_COLOR_NUM 20
 
int color_num;
int gray_vol;
int color_vol[MAX_COLOR_NUM];
int ans;
 
void input()
{
    int max_vol = ;
    for (int i = ; i < color_num; i++)
    {
        scanf("%d", &color_vol[i]);
        max_vol = max(color_vol[i], max_vol);
    }
    scanf("%d", &gray_vol);
    ans = (max_vol + ) / ;
}
 
void produce_gray()
{
    priority_queue<int> pq;
    for (int i = ; i < color_num; i++)
        if (color_vol[i] != )
        {
            pq.push(color_vol[i]);
            color_vol[i] = ;
        }
    while (pq.size() >= )
    {
        int a = pq.top();
        pq.pop();
        int b = pq.top();
        pq.pop();
        int c = pq.top();
        pq.pop();
        a--;
        b--;
        c--;
        gray_vol--;
        if (a)
            pq.push(a);
        if (b)
            pq.push(b);
        if (c)
            pq.push(c);
    }
    int i = ;
    while (!pq.empty())
    {
        color_vol[i] = pq.top();
        pq.pop();
        i++;
    }
}
 
void work()
{
    for (int i = ; i < color_num; i++)
        color_vol[i] = ans *  - color_vol[i];
    while ()
    {
        produce_gray();
        if (gray_vol <= )
            break;
        ans++;
        for (int i = ; i < color_num; i++)
            color_vol[i] += ;
    }
    printf("%d\n", ans);
}
 
int main()
{
    while (scanf("%d", &color_num), color_num)
    {
        input();
        work();
    }
    return ;
}