HDU 1051 与1257类似 二维排序，然后贪心

#include <cstdio>
#include <string>
#include <algorithm>
#include <iostream>
using namespace std;

typedef struct
{
int x, y;
} node;

bool cmp(node n1, node n2)
{
if(n1.x != n2.x)
return (n1.x < n2.x);
else
return (n1.y < n2.y);
}
node a[5010];
int len = 0;

int min(int *b)
{
int min = 1000000;
for(int i = 0; i < len; i++)
{
if(min > b[i])
min = b[i];
}
return min;
}

int maxIndex(int *b, int a)
{
int max = 0;
int index = 0;
for(int i = len -1; i >= 0; i--)
{
if(b[i] <= a && b[i] >= max)
{
max = b[i];
index = i;
}
}
return index;
}
int main()
{
int t;
cin >> t;
while(t--)
{
len = 0;
int n;
cin >> n;
int *b = new int[n+1];
for(int i = 0; i < n; i++)
{
scanf("%d%d", &a[i].x, &a[i].y);
}
sort(a, a+n, cmp);
for(int i = 0; i < n; i++)
{
if(a[i].y < min(b))
{
b[len++] = a[i].y;
}
else
{
b[maxIndex(b, a[i].y)] = a[i].y;
}
}
cout << len << endl;
delete [] b;
}
return 0;
}