学步园

题目链接：zoj2136

讲当前最长上升子序列建一个数组，利用二分查找

#include<iostream>
using namespace std;

const int maxn = 1002;

int a[maxn];

int find(int *a,int len,int n)
{
	int left = 0,right=len,mid=(left+right)/2;
	while(left<=right)
	{
		if(a[mid] < n)
			left = mid + 1;
		else if(a[mid] > n)
			right = mid - 1;
		else
			return mid;
		mid = (left+right)/2;
	}
	return left;
}

int main(void)
{
	int ncases,n;
	cin>>ncases;
	while(ncases--)
	{
		cin>>n;
		for(int i=0;i<n;i++)
			cin>>a[i];
		int c[n+1];
		c[0] = -1;
		c[1] = a[0];
		int len = 1;
		for(int i=1;i<n;i++)
		{
			int j = find(c,len,a[i]);
			c[j] = a[i];
			if(j > len)
				len = j;
		}
		cout<<len<<endl;
		if(ncases)
			cout<<endl;
	}
	return 0;
}