NYOJ-16-矩形嵌套 记忆化搜索

#include<iostream>
#include<stdio.h>
#include<string.h>
#include<algorithm>
#define rep(i,j,k) for(int i=j;i<=k;i++)
using namespace std;
const int maxx =1005;
int maps[maxx][maxx];
int d[maxx];
struct node{
   int x,y;
}a[maxx];
int n;
int dp(int i){
   int& ans=d[i];
   if(ans>0)return ans;
   ans=1;
   for(int j=1;j<=n;j++){
      if (maps[j][i])ans=max(ans,dp(j)+1);
   }
   return ans;
}
int main(){
   int t;
  scanf("%d",&t);
  while(t--){
    scanf("%d",&n);
    memset(maps,0,sizeof(maps));
    for (int i=1;i<=n;i++){
        scanf("%d%d",&a[i].x,&a[i].y);
        if (a[i].x<a[i].y)swap(a[i].x,a[i].y);
    }
    rep(i,1,n)
    {
       rep(j,1,n){
         if ((a[i].x>a[j].x)  && (a[i].y>a[j].y)){
            maps[i][j]=1;
         }
       }
    }
    int ans=0;
    memset(d,0,sizeof(d));
    rep(i,1,n){
       ans=max(ans,dp(i));
    }
    printf("%d\n",ans);
  }
  return 0;
}