HDU-1500 Chopsticks DP

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我是靠谱客的博主苹果吐司，这篇文章主要介绍HDU-1500 Chopsticks DP，现在分享给大家，希望可以做个参考。

http://acm.hdu.edu.cn/showproblem.php?pid=1500

与上一题搬寝室基本一样多点条件而已！

状态：

dp[i][j]表示前i个取j组

转移方程：

dp[i][j] = Min( dp[i-2][j-1] + (w[i] - w[i-1])*(w[i] - w[i-1]),dp[i-1][j] );

dp[i%3][j] = Min( dp[(i-2)%3][j-1] + (w[i] - w[i-1])*(w[i] - w[i-1]),dp[(i-1)%3][j] ); // 滚动数组

复制代码

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#include <stdio.h>
#include <string.h>
#include <queue>
#include <algorithm>
using namespace std;
const int maxn = 5005;
const int inf = 1<<30;
int n,k;
int w[maxn],dp[maxn][1005];

int Min(int a,int b)
{
    return a<b?a:b;
}

int getDP()
{
    for( int i = 0; i <= n; i ++ )
        for( int j = 1; j <= k; j ++ )
            dp[i][j] = inf;

    for( int i = 3; i <= n; i ++ )
    {
        for( int j = 1; j <= i/3; j ++ )
        {
            dp[i][j] = Min( dp[i-2][j-1] + (w[i] - w[i-1])*(w[i] - w[i-1]),dp[i-1][j] );
        }
    }
    return dp[n][k];
}
int main()
{
    int t;
    scanf("%d",&t);
    while( t-- )
    {
        scanf("%d%d",&k,&n);
        for( int i = n; i >= 1; i ++ )
        {
            scanf("%d",&w[i]);
        }

        k += 8;

        printf("%dn",getDP());
    }
    return 0;
}

滚动数组版

复制代码

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#include <stdio.h>
#include <string.h>
#include <queue>
#include <algorithm>
using namespace std;
const int maxn = 5005;
const int inf = 1<<30;
int n,k;
int w[maxn],dp[maxn][1005];

int getDP()
{
    for( int i = 0; i <= n; i ++ )
        for( int j = 1; j <= k; j ++ )
            dp[i][j] = inf;

    for( int i = 3; i <= n; i ++ )
    {
        for( int j = 1; j <= i/3; j ++ )
        {
            dp[i][j] = min( dp[i-2][j-1] + (w[i] - w[i-1])*(w[i] - w[i-1]),dp[i-1][j] );
        }
    }
    return dp[n][k];
}
int main()
{
    int t;
    scanf("%d",&t);
    while( t-- )
    {
        scanf("%d%d",&k,&n);
        for( int i = n; i >= 1; i -- )
        {
            scanf("%d",&w[i]);
        }
        k += 8;
        printf("%dn",getDP());
    }
    return 0;
}