HDU 1081 DP Problem: Maximum sub-matrix and

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Test instructions: give you a n*n matrix, find the maximum sub-matrices of this matrix and

#include <iostream> #include <cstdio> #include <string.h>using namespace std; #define INF- 0x3f3f3f3fint Field[105][105],dp[105];int Main () {    int n;    while (~SCANF ("%d", &n))    {        int maxn=0;        memset (field,0,sizeof (field));        Memset (Dp,0,sizeof (DP));        for (int i=1;i<=n;i++)          for (int j=1;j<=n;j++)            {                scanf ("%d", &field[i][j]);                FIELD[I][J]+=FIELD[I-1][J];            } Process the first I and for       (int i=1;i<=n;i++) for         (int j=0;j<i;j++)//enumeration set two frames for            (int k=0;k<=n;k++)//Run DP            {                dp[k]=field[i][k]-field[j][k];                if (dp[k-1]>0)                    dp[k]+=dp[k-1];                Maxn=max (Maxn,dp[k]);            }        printf ("%d\n", MAXN);    }    return 0;}

Analysis: Classic DP problem: To find the maximum subsequence and, but this problem of deformation is no longer a one-dimensional, but two-dimensional, so need to set

Take a look at the two frames and then run one-dimensional DP between the two frames, a very ingenious idea! DP is used to hold the maximum value of the previous matrix

HDU 1081 DP Problem: Maximum sub-matrix and