zoj2136 最长上升子序列LIS O(NlgN)解法

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;elsereturn 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;}