(贪心5.2.3)POJ 1065 Wooden Sticks(利用数据有序化来进行贪心选择)

/*
 * POJ_1064.cpp
 *
 *  Created on: 2013年10月10日
 *      Author: Administrator
 */

#include <iostream>
#include <cstdio>

using namespace std;

const int maxn = 5010;

struct node{
	int l,w;
	bool isUsed;

	bool operator>(node &n){
		return l > n.l ||(l == n.l && w > n.w);
	}

	node& operator=(node &n){
		l = n.l , w = n.w , isUsed = n.isUsed;

		return *this;
	}

	void swap(node& n){
		node tmp = *this;
		*this = n;
		n = tmp;
	}

}A[maxn];


int main(){
	int t;
	scanf("%d",&t);
	while(t--){
		int n;
		scanf("%d",&n);

		int i;
		for(i = 0 ; i < n ; ++i){
			scanf("%d%d",&A[i].l,&A[i].w);
			A[i].isUsed = false;
		}

		int j,k;
		for(j = 1; j < n ; ++j){
			for(k = 1 ; k <= n - j ; ++k){
				if(A[k-1] > A[k]){
					A[k-1].swap(A[k]);
				}
			}
		}

		node cur = A[0];
		A[0].isUsed = true;
		int c = 0;

		while(true){
			for(j = 1 ; j < n ; ++j){
				if(A[j].isUsed == false ){
					if(A[j].l >= cur.l && A[j].w >= cur.w){
						A[j].isUsed = true;
						cur = A[j];
					}
				}
			}

			c++;

			for(j = 1 ; j < n ; ++j){
				if(A[j].isUsed == false){
					cur = A[j];
					A[j].isUsed = true;
					break;
				}
			}

			if(j == n){
				break;
			}
		}

		printf("%d\n",c);
	}

	return 0;
}