UVA - 11997 K Smallest Sums

1.题面

http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=18702

2.题意

给你k个数组,每个数组有k个元素.

现在从k个数组中每个都选取1个数字出来,共有k^k种选法

求这k^k个选法中,最小的k个是多少.

3.思路

采用的是刘汝佳大白中的方法.

基本没什么我自己的想法,所以也没什么好说的,不过值得一提的是,这段代码应该是有机会修改成选取最小的任意个个数字的.

4.代码

/*****************************************************************    > File Name: Cpp_Acm.cpp    > Author: Uncle_Sugar    > Mail: [e-mail]    > Created Time: 2016年05月12日 星期四 13时37分31秒*****************************************************************/# include <cstdio># include <cstring># include <cctype># include <cmath># include <cstdlib># include <climits># include <iostream># include <iomanip># include <set># include <map># include <vector># include <stack># include <queue># include <algorithm>using namespace std;const int debug = 1;const int size  = 1000 + 10; const int INF = INT_MAX>>1;typedef long long ll;int a[size];int b[size];struct Item{int s,b;Item(){}Item(int s,int b):s(s),b(b){}bool operator < (const Item& cmper)const{return s > cmper.s;}};priority_queue<Item> pri_que;void Merge(int *A,int *B,int *C,int n){while (!pri_que.empty())pri_que.pop();for (int i=0;i<n;i++){pri_que.push(Item(A[i]+B[0],0));}for (int i=0;i<n;i++){Item T = pri_que.top();pri_que.pop();C[i] = T.s;if (T.b+1<n)pri_que.push(Item(T.s - B[T.b] + B[T.b+1],T.b+1));}}int main(){std::ios::sync_with_stdio(false);cin.tie(0);int i,j;int n;while (cin >> n){for (i=0;i<n;i++)cin >> a[i];sort(a,a+n);for (i=1;i<n;i++){for (j=0;j<n;j++)cin >> b[j];sort(b,b+n);Merge(a,b,a,n);}for (i=0;i<n;i++){cout << a[i] << (i==n-1?'\n':' ');}}return 0;}