Longest Ordered Subsequence

#include<iostream>
#include<cstdio>
#include<memory>
#include<cstring>
#include<algorithm>
using namespace std;
#define INF 10005
int num[1005],re[1005];
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        for(int i=0; i<n; ++i)
            scanf("%d",&num[i]);
        for(int i=1; i<=n; ++i)
            re[i]=INF;
        int ans=0;
        for(int i=0; i<n; ++i)
        {
            int k=lower_bound(re+1,re+1+n,num[i])-re;
            re[k]=num[i];
            ans=max(ans,k);
        }
        printf("%d\n",ans);
    }
}