解題區/解題區 - UVa

UVa 11851 - Celebrity Split

contents

  1. 1. Problem
  2. 2. Sample Input
  3. 3. Output for Sample Input
  4. 4. Solution

Problem

家產劃分給兩個人，兩個人分配的房子總價值必須相同，剩下無法劃分的房子將換成現金分配給兩個人，求換成現金的總額最小為何？

Sample Input

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6000000
30000000
3000000
11000000
3000000
0

Output for Sample Input

1
41000000

Solution

窮舉分配情況，並且試圖將後期分配肯定會失敗的情況剪掉。

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#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
#include <functional>
using namespace std;
int n;
long long A[32], suffix[32], ret;
void dfs(int i, long long x, long long y, long long sold) {
    if(sold >= ret || abs(x - y) > suffix[i])	return;
    if(x == y)
        ret = min(ret, sold + suffix[i]);
    if(i == n)
        return;
    if(x == y) {
        dfs(i+1, x + A[i], y, sold);
        dfs(i+1, x, y, sold + A[i]);
    } else {
        dfs(i+1, x + A[i], y, sold);
        if(x)
            dfs(i+1, x, y + A[i], sold);
        dfs(i+1, x, y, sold + A[i]);
    }
}
int main() {
    while(scanf("%d", &n) == 1 && n) {
        for(int i = 0; i < n; i++)
            scanf("%lld", &A[i]);
        sort(A, A+n, greater<long long>());
        suffix[n] = 0;
        for(int i = n-1; i >= 0; i--)
            suffix[i] = suffix[i+1] + A[i];
        ret = 1LL<<60;
        dfs(0, 0, 0, 0);
        printf("%lld\n", ret);
    }
    return 0;
}