POJ 1836 Alignment

目前WA中，正在找错……

#include <cstdio>

const int MAXN = 1000 + 10;
const int INF = 2147483645;

double stack[MAXN];
double height[MAXN];
double reverse[MAXN];
int n;

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

int DP( int y, double *num )              //求到位置 y - 1 的最长上升子序列
{
    int top = 0;

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

    for ( int i = 1; i < y; i++ )
    {
        if ( num[i] > stack[top] )
            stack[ ++top ] = num[i];
        else
        {
            int temp = Bsearch( 0, top, num[i] );
            if ( stack[temp] > num[i] ) stack[temp] = num[i];
            else stack[temp + 1] = num[i];
        }
    }

    return top;
}

int main()
{
    while ( scanf("%d", &n) != EOF )
    {
        for ( int i = 0; i < n; i++ )
        {
            scanf( "%lf", &height[i] );
            reverse[n - 1 - i] = height[i];      //逆序存一下该数列，把求从左往右的递减序列问题
                                                 //转换为求从右往左的递增序列问题
        }

        int MIN = INF;
        for ( int i = 0; i < n; i++ )
        {
            int temp;
            int ans1 = DP( i, height );
            int ans2 = DP( n - i, reverse );

            temp = n - ( ans1 + ans2 );

//            printf( "%d %d\n", ans1, ans2 );

            if ( temp < MIN ) MIN = temp;
        }

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