poj 3903 poj 2533 （LIS模板题）

pi1 < pi2 < ... < pik, with i1 < i2 < ... < ik.

Sample Input

6
5 2 1 4 5 3
3
1 1 1
4
4 3 2 1
Sample Output

3
1
1

# include <iostream>
# include <cstdio>
# include <cstring>
# include <algorithm>
# include <cmath>
# define LL long long
using namespace std ;

int a[100010] ;
int f[100010] ;
//int dp[100010] ;
int n ;

int bsearch(int size, const int &a) {
    int l=0, r=size-1;
    while( l <= r ){
        int mid = (l+r)/2;
        if( a > f[mid-1] && a <= f[mid] ) return mid;// >&&<= 换为: >= && <
        else if( a < f[mid] ) r = mid-1;
        else l = mid+1;
    }
}

int LIS()
{
    int i, j, size = 1;
    f[0] = a[0];
    //dp[0] = 1;
    for( i=1; i < n; ++i )
    {
        if( a[i] <= f[0] ) j = 0; // <= 换为: <
        else if( a[i] > f[size-1] ) j = size++;// > 换为: >=
        else j = bsearch(size, a[i]);
        f[j] = a[i];
        //dp[i] = j+1;
    }
    return size;
}


int main ()
{
  //  freopen("in.txt","r",stdin) ;
    while(scanf("%d" , &n) !=EOF)
    {
        int i ;
        for (i = 0; i < n ; i++)
            scanf("%d" , &a[i]) ;
        printf("%d
" , LIS()) ; // 求最大递增/上升子序列(如果为最大非降子序列,只需把上面的注释部分给与替换)
    }


    return 0 ;
}