poj 1088 dp **

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 1 #include<cstdio>

 2 #include<iostream>

 3 #include<algorithm>

 4 #include<cstring>

 5 #include<cmath>

 6 #include<queue>

 7 #include<map>

 8 using namespace std;

 9 #define MOD 1000000007

10 const int INF=0x3f3f3f3f;

11 const double eps=1e-5;

12 typedef long long ll;

13 #define cl(a) memset(a,0,sizeof(a))

14 #define ts printf("*****\n");

15 const int MAXN=1005;

16 int n,m,tt;

17 int a[MAXN][MAXN];

18 int dp[MAXN][MAXN];

19 int d[4][2]={1,0,0,1,-1,0,0,-1};

20 int fun(int x,int y)

21 {

22     if(dp[x][y]>0)    return dp[x][y];

23     dp[x][y]=1;

24     for(int i=0;i<4;i++)

25     {

26         int nx=x+d[i][0];

27         int ny=y+d[i][1];

28         if(nx>=1&&nx<=n&&ny>=1&&ny<=m&&a[x][y]>a[nx][ny])

29         {

30             if(dp[x][y]<fun(nx,ny)+1)

31                 dp[x][y]=dp[nx][ny]+1;

32         }

33     }

34     return dp[x][y];

35 }

36 int main()

37 {

38     int i,j,k;

39     #ifndef ONLINE_JUDGE

40     freopen("1.in","r",stdin);

41     #endif

42     while(scanf("%d%d",&n,&m)!=EOF)

43     {

44         for(i=1;i<=n;i++)

45         {

46             for(j=1;j<=m;j++)

47             {

48                 scanf("%d",&a[i][j]);

49             }

50         }

51         memset(dp,-1,sizeof(dp));

52         int ans=0;

53         for(i=1;i<=n;i++)

54             for(j=1;j<=m;j++)

55             {

56                 if(fun(i,j)>ans) ans=dp[i][j];

57             }

58         printf("%d\n",ans);

59     }

60 }