ZOJ 1986 Bridging Signals

题目链接：http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=986

最长上升子序列……

#include <cstdio>
#include <cstring>

const int MAXN = 40000 + 10;

int n;
int num[MAXN];
int stack[MAXN];

int Bsearch( int x, int y, int v )
{
    int m;
    while ( x < y )
    {
        m = x + (y - x) / 2;
        if ( stack[m] == v ) return m;
        else if ( stack[m] > v ) y = m;
        else x = m + 1;
    }
    return m;
}

int DP()
{
    int top = 0;

    stack[ ++top ] = num[0];

    for ( int i = 1; i < n; i++ )
    {
        if ( num[i] > stack[top] ) stack[ ++top ] = num[i];
        else
        {
            int temp = Bsearch( 1, top + 1, num[i] );
            if (stack[temp] > num[i])
                stack[temp] = num[i];
            else stack[temp + 1] = num[i];
        }
    }

    return top;
}

int main()
{
    int T;
    scanf("%d", &T);
    while ( T-- )
    {
        scanf( "%d", &n );
        for ( int i = 0; i < n; i++ )
            scanf( "%d", &num[i] );

        printf( "%d\n", DP() );
    }
    return 0;
}