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It's a LCS problem,I think I am absolutely right.But why TLE!!!Please help me!Thank you very much!!!
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int d[1010][1010];
char a[1010],b[1010];
int dp(int i,int j){
if(i<0||j<0) return 0;
int &ans=d [j];
if(ans>0)return ans ...