poj 1088 动态规划

#include<iostream>#include<cstring>using namespace std;int a[100][100],b[100][100];int r,c;int  DP(int i,int j){int ans=0;if(b[i][j]==0){if(i>0){if(a[i][j]>a[i-1][j])ans=ans>DP(i-1,j)?ans:DP(i-1,j);}if(i+1<r){if(a[i][j]>a[i+1][j])ans=ans>DP(i+1,j)?ans:DP(i+1,j);}if(j>0){if(a[i][j]>a[i][j-1])ans=ans>DP(i,j-1)?ans:DP(i,j-1);}if(j+1<c){if(a[i][j]>a[i][j+1])ans=ans>DP(i,j+1)?ans:DP(i,j+1);}b[i][j]=1+ans;}return b[i][j];}int main(){int i,j,max=0;cin>>r>>c;memset(b,0,sizeof(b));for(i=0;i<r;i++)for(j=0;j<c;j++)cin>>a[i][j];   //这个地方写成了a[i][c],害我调了几个小时。。。。。。for(i=0;i<r;i++)for(j=0;j<c;j++){if(max<DP(i,j))max=DP(i,j);}cout<<max<<endl;return 0;}