【HDU】5777 - domino（贪心）

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domino

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 688 Accepted Submission(s): 353

Problem Description

Little White plays a game.There are n pieces of dominoes on the table in a row. He can choose a domino which hasn't fall down for at most k times, let it fall to the left or right. When a domino is toppled, it will knock down the erect domino. On the assumption that all of the tiles are fallen in the end, he can set the height of all dominoes, but he wants to minimize the sum of all dominoes height. The height of every domino is an integer and at least 1.

Input

The first line of input is an integer T ( ) There are two lines of each test case. The first line has two integer n and k, respectively domino number and the number of opportunities.( ) The second line has n - 1 integers, the distance of adjacent domino d,

Output

For each testcase, output of a line, the smallest sum of all dominoes height

Sample Input

   1
4 2
2 3 4

Sample Output

   9

Source

BestCoder Round #85

多找几组例子试一下就发现了结果，就是贪心思想让最远的牌单独推。

代码如下：

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>
using namespace std;
#define INF 0x3f3f3f3f
#define CLR(a,b) memset(a,b,sizeof(a))
int main()
{
    int n,k;
    int u;
    int num[100000+11];
    __int64 sum;
    scanf ("%d",&u);
    while (u--)
    {
        scanf ("%d %d",&n,&k);
        sum = 0;
        for (int i = 1 ; i < n ; i++)
        {
            scanf ("%d",&num[i]);
            sum += num[i];
        }
        if (k >= n)
        {
            printf ("%d\n",n);
            continue;
        }
        sort (num+1,num+n);
        for (int i = n - 1 , j = 1 ; j < k ; i-- , j++)
            sum -= num[i];
        sum += n;
        printf ("%I64d\n",sum);
    }
    return 0;
}