[NYIST16]矩形嵌套（DP，最长上升子序列）

题目链接：http://acm.nyist.net/JudgeOnline/problem.php?pid=16

像套娃一样把矩形套起来。先给矩形从小到大排序，然后做最长上升子序列就行

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 */
 #include <algorithm>
 #include <iostream>
 #include <iomanip>
 #include <cstring>
 #include <climits>
 #include <complex>
 #include <fstream>
 #include <cassert>
 #include <cstdio>
 #include <bitset>
 #include <vector>
 #include <deque>
 #include <queue>
 #include <stack>
 #include <ctime>
 #include <set>
 #include <map>
 #include <cmath>
 using namespace std;
 #define fr first
 #define sc second
 #define cl clear
 #define BUG puts("here!!!")
 #define W(a) while(a--)
 #define pb(a) push_back(a)
 #define Rint(a) scanf("%d", &a)
 #define Rll(a) scanf("%I64d", &a)
 #define Rs(a) scanf("%s", a)
 #define Cin(a) cin >> a
 #define FRead() freopen("in", "r", stdin)
 #define FWrite() freopen("out", "w", stdout)
 #define Rep(i, len) for(LL i = 0; i < (len); i++)
 #define For(i, a, len) for(LL i = (a); i < (len); i++)
 #define Cls(a) memset((a), 0, sizeof(a))
 #define Clr(a, x) memset((a), (x), sizeof(a))
 #define Fuint(a) memset((a), 0x7f7f, sizeof(a))
 #define lrt rt << 1
 #define rrt rt << 1 | 1
 #define pi 3.14159265359
 #define RT return
 #define lowbit(x) x & (-x)
 #define onenum(x) __builtin_popcount(x)
 typedef long long LL;
 typedef long double LD;
 typedef unsigned long long Uint;
 typedef pair<LL, LL> pii;
 typedef pair<string, LL> psi;
 typedef map<string, LL> msi;
 typedef vector<LL> vi;
 typedef vector<LL> vl;
 typedef vector<vl> vvl;
 typedef vector<bool> vb;

 typedef struct Square {
     int x, y;
     Square() {}
     Square(int xx, int yy) : x(xx), y(yy) {}
 }Square;

 const int maxn = ;
 Square s[maxn];
 int n;
 int dp[maxn];

 bool cmp(Square a, Square b) {
     if(a.x == b.x) return a.y <= b.y;
     return a.x < b.x;
 }

 bool ok(Square a, Square b) {
     return a.x > b.x && a.y > b.y;
 }

 int main() {
     // FRead();
     int T, x, y;
     Rint(T);
     W(T) {
         Cls(dp);
         Rint(n);
         For(i, , n+) {
             Rint(x); Rint(y);
             if(x > y) swap(x, y);
             s[i] = Square(x, y);
         }
         sort(s+, s+n+, cmp);
         int ret = ;
         For(i, , n+) {
             dp[i] = ;
             For(j, , i+) {
                 if(ok(s[i], s[j])) {
                     dp[i] = max(dp[i], dp[j]+);
                 }
             }
             ret = max(dp[i], ret);
         }
         printf("%d\n", ret+);
     }
     RT ;
 }