Brute Force - B. Candy Boxes ( Codeforces Round #278 (Div. 2)

B. Candy Boxes

Problem's Link:   http://codeforces.com/contest/488/problem/B

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Mean:

T题目意思很简单，不解释。

analyse:

这道题还是很有意思的，需要考虑到各种情况才能AC。

解这个题目之前，首先要推出两条式子

　　x4=3x1
　　4x1=x2+x3

然后就是分类讨论，枚举各种情况就可。

Time complexity: O(1)

Source code: 

//  Memory   Time
//  1347K     0MS
//   by : Snarl_jsb
//   2014-11-26-21.20
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<vector>
#include<queue>
#include<stack>
#include<map>
#include<string>
#include<climits>
#include<cmath>
#define N 1000010
#define LL long long
using namespace std;

int ans[10], input[10];
bool flag = true;
bool Solve(int n)
{
    if (n == 0)
    {
        puts("YES");
        printf("%d\n%d\n%d\n%d\n", 1, 1, 3, 3);
    }
    if (n == 1)
    {
        puts("YES");
        ans[1] = input[1], ans[4] = ans[1] * 3, ans[2] = ans[1], ans[3] = ans[4];
        for (int i = 2; i <= 4; i++) printf("%d\n", ans[i]);
    }
    if (n == 2)
    {
        if (input[2] % 3)
        {
            if (input[1] * 3 < input[2]) return flag = false;
            puts("YES");
            ans[1] = input[1], ans[4] = ans[1] * 3;
            int tmp = 4 * ans[1] - input[2];
            printf("%d\n%d\n", ans[4], tmp);
        }
        else
        {
            if (input[2] / 3 > input[1]) return flag = false;
            puts("YES");
            ans[1] = input[2] / 3;
            int tmp = 4 * ans[1] - input[1];
            printf("%d\n%d\n", ans[1], tmp);
        }
    }
    if (n == 3)
    {
        if (input[3] % 3)
        {
            if (input[1] * 3 < input[3]) return flag = false;
            for (int i = 1; i <= 3; i++) ans[i] = input[i];
            ans[4] = ans[1] * 3;
            if (4 * ans[1] != ans[2] + ans[3]) return flag = false;
            puts("YES");
            printf("%d\n", ans[4]);
        }
        else
        {
            if (input[3] / 3 > input[1]) return flag = false;
            if (input[3] / 3 == input[1])
            {
                puts("YES");
                printf("%d\n", input[1] * 4 - input[2]);
                return true;
            }
            ans[1] = input[3] / 3, ans[4] = input[3], ans[2] = input[1], ans[3] = input[2];
            if (4 * ans[1] != ans[2] + ans[3]) return flag = false;
            puts("YES");
            printf("%d\n", ans[1]);
        }
    }
    if (n == 4)
    {
        for (int i = 1; i <= 4; i++) ans[i] = input[i];
        if (4 * ans[1] == ans[2] + ans[3]) puts("YES");
        else flag = false;
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
//    freopen("C:\\Users\\ASUS\\Desktop\\cin.cpp","r",stdin);
//    freopen("C:\\Users\\ASUS\\Desktop\\cout.cpp","w",stdout);
    int n, i, j;
    scanf("%d", &n);
    for (i = 1; i <= n; i++) scanf("%d", &input[i]);
    sort(input + 1, input + n + 1);
    Solve(n);
    if (!flag)
    {
        puts("NO");
        return 0;
    }
    return 0;
}
/*

*/