bzoj 1084: [SCOI2005]最大子矩阵

Posted 2021-02-05 lxy8584099

分情况

 

/**************************************************************
    Problem: 1084
    User: lxy8584099
    Language: C++
    Result: Accepted
    Time:84 ms
    Memory:2004 kb
****************************************************************/
 
/*
    m==1 f[i][j]表示前i个数中取出j个矩形的最大和
    m==2 w[i][j][k]表示第一列选到第i个数，第二列选到第j个数时，总共k个子矩形的答案
*/
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;
#define MAXN 110
#define INF 32768
int n,m,K,a;
int f[MAXN][15],w[MAXN][MAXN][15],s[MAXN],sum[MAXN][2];
int main()
{
    scanf("%d%d%d", &n, &m, &K);
    if (m==1)
    {
        for (int i=1;i<=n;i++)
        {
            scanf("%d", &a);
            s[i]=s[i-1]+a;
        }
        for (int i=0;i<=n;i++)
            for (int j=1;j<=K;j++) f[i][j]=-INF;
        for (int i=1;i<=n;i++)
            for (int j=1;j<=K;j++)
        {
            f[i][j]=f[i-1][j];
            for (int i1=0;i1<i;i1++)
                f[i][j]=max(f[i][j],f[i1][j-1]+s[i]-s[i1]);
        }
        printf("%d", f[n][K]);
    }
    else
    {
        for (int i=1;i<=n;i++)
            for (int j=1;j<=m;j++)
        {
            scanf("%d", &a);
            sum[i][j]=sum[i-1][j]+a;
        }
        for (int i=0;i<=n;i++)
            for (int j=0;j<=n;j++)
            for (int k=1;k<=K;k++) w[i][j][k]=-INF;
        for (int i=1;i<=n;i++)
            for (int j=1;j<=n;j++)
                for (int k=1;k<=K;k++)
        {
            w[i][j][k]=max(w[i-1][j][k],w[i][j-1][k]);
            for (int i1=0;i1<i;i1++)
                w[i][j][k]=max(w[i1][j][k-1]+sum[i][1]-sum[i1][1],w[i][j][k]);
            for (int j1=0;j1<j;j1++)
                w[i][j][k]=max(w[i][j1][k-1]+sum[j][2]-sum[j1][2],w[i][j][k]);
            if (i==j)
            {
                for (int i1=0;i1<i;i1++)
                    w[i][i][k]=max(w[i][i][k],w[i1][i1][k-1]+sum[i][1]+sum[i][2]-sum[i1][1]-sum[i1][2]);
            }
        }
        printf("%d", w[n][n][K]);
    }
}