hdu 5747 最长上升子序列 （nlogn)

ac code:

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
using namespace std;
typedef long long ll;
#define INF 1e9
#define maxn 100005
int a[maxn];              //记录原序列
int d[maxn];              //d[k] 表示长度为k的上升子序列结尾的最小值
int f[maxn];              //f[t] 表示以a[t]结尾的上升子序列的最大长度

int main()
{
    int n,m;
    int cas;
    cin >> cas;
    while(cas --){
        cin >> n;
        for(int i = 1;i <= n;i ++){
            cin >> a[i];
        }
        //nlogn 的dp 求最长公共子串
        for(int i = 1;i <= n;i ++){
            d[i] = INF;
            f[i] = 1;
        }
        int nowK = 1;
        for(int i = 1;i <= n;i ++){
            int l,r;
            l = 1;
            r = i+1;
            while(l <= r){
                int m = (l+r)/2;
                if(a[i] > d[m]) l = m + 1;
                else r = m - 1;
            }
            f[i] = l;
            d[l] = a[i];
        }
        for(int i = 1;i <= n-1;i ++)
            printf("%d ",f[i]);
        printf("%d
",f[n]);
    }
    return 0;
}