hdu1505 dp

  1 //Accepted    5196 KB    109 ms
  2 //类似hdu1506
  3 //输入数据的格式没有明确的限制
  4 //可能出现以下情况
  5 //5 5
  6 //R
  7 //F
  8 //F F F
  9 //F F F F F
 10 //R R R
 11 //R R
 12 //R F R F R
 13 //R R R R R
 14 #include <cstdio>
 15 #include <cstring>
 16 #include <iostream>
 17 using namespace std;
 18 const int imax_n = 1005;
 19 bool map[imax_n][imax_n];
 20 int a[imax_n][imax_n];
 21 int l[imax_n],r[imax_n];
 22 int n,m;
 23 void getA()
 24 {
 25     for (int i=1;i<=n;i++)
 26     {
 27         for (int j=1;j<=m;j++)
 28         {
 29             a[i][j]=0;
 30             int t=i;
 31             while (t>0 && map[t][j]==1)
 32             {
 33                 a[i][j]++;
 34                 t--;
 35             }
 36         }
 37     }
 38    // for (int i=1;i<=n;i++)
 39     //{
 40     //    for (int j=1;j<=m;j++)
 41     //    printf("%d ",a[i][j]);
 42     //    printf("\n");
 43     //}
 44 }
 45 void Dp()
 46 {
 47     getA();
 48     int ans=0;
 49     for (int i=1;i<=n;i++)
 50     {
 51         l[1]=1;
 52         a[i][0]=-1;
 53         for (int j=2;j<=m;j++)
 54         {
 55             int t=j;
 56             while (a[i][j]<=a[i][t-1])
 57             {
 58                 t=l[t-1];
 59             }
 60             l[j]=t;
 61         }
 62         r[m]=m;
 63         a[i][m+1]=-1;
 64         for (int j=m-1;j>=1;j--)
 65         {
 66             int t=j;
 67             while (a[i][j]<=a[i][t+1])
 68             {
 69                 t=r[t+1];
 70             }
 71             r[j]=t;
 72         }
 73         for (int j=1;j<=m;j++)
 74         if (a[i][j]*(r[j]-l[j]+1)>ans)
 75         ans=a[i][j]*(r[j]-l[j]+1);
 76     }
 77     printf("%d\n",3*ans);
 78 }
 79 char s[5];
 80 int main()
 81 {
 82     int T;
 83     while (scanf("%d",&T)!=EOF)
 84     {
 85         while (T--)
 86         {
 87             scanf("%d%d",&n,&m);
 88             for (int i=1;i<=n;i++)
 89             {
 90                 for (int j=1;j<=m;j++)
 91                 {
 92                     scanf("%s",s);
 93                     if (s[0]==‘F‘)
 94                     map[i][j]=1;
 95                     else
 96                     map[i][j]=0;
 97                 }
 98             }
 99         //for (int i=1;i<=n;i++)
100         //{
101          //   for (int j=1;j<=m;j++)
102          //   printf("%d",map[i][j]);
103          //   printf("\n");
104         //}
105             Dp();
106         }
107     }
108     return 0;
109 }