pku 2761

pku 2761

从昨天到今天。。。。
我不明白。。为什么一直错。。。我现在还是不明白。。
这是我写这类问题。。似乎都会出现的问题。。要把数组开单很多很多倍。。我到现在还是不明白这是为什么





还是第一次能在第一页的呢。。呵呵。。小安慰一下

#include < iostream >
#include < algorithm >
#define MaxN  300005
             
#define MaxM  200005
using namespace std;
int  N,M,res[MaxM];
struct node
{
     int  pri,n;
    friend bool operator < (node a,node b)
    {
        return a.pri < b.pri;
    }
}index[MaxN],ii[MaxN];
struct line
{
     int  b,e,k,n,ans;
    friend bool operator < (line a,line b)
    {
        return a.b < b.b;
    }
}Line[MaxM];
int  cc[MaxN];
void inser_del( int  key, int  flag)
{
     int  L = 0 ,R = N - 1 , mid ,v = 1 ;
     while (L < R)
    {
        cc[v] += flag;
         mid = (L + R) / 2 ;
        v *= 2 ;
         if (key <= mid )
            R = mid ;
         else
        {
            v ++ ;
            L = mid + 1 ;
        }
    }
    cc[v] += flag;
}
int  solve( int  k)
{
     int  L = 0 ,R = N - 1 , mid ,v = 1 ;
     while (L < R)
    {
         mid = (L + R) / 2 ;
         if (cc[ 2 * v] >= k)
        {
            R = mid ;
            v *= 2 ;
        }
         else  
        {
            L = mid + 1 ;
            k -= cc[ 2 * v];
            v = 2 * v + 1 ;
        }
    }
    return index[L].pri;
}

int  main()
{
     int  i,j;
    scanf( " %d%d " , & N, & M);

         for (i = 0 ;i < N;index[i].n = i ++ )
            scanf( " %d " , & index[i].pri);
         for (i = 0 ;i < M;Line[i].n = i ++ )
        {
            scanf( " %d%d%d " , & Line[i].b, & Line[i].e, & Line[i].k);
             if (Line[i].b > Line[i].e)swap(Line[i].b,Line[i].e);
             -- Line[i].b;
             -- Line[i].e;
        }
         // 初始化 --> cc为0
        sort(index,index + N);
        sort(Line,Line + M);
        
         for (i = 0 ;i < N;i ++ )
        {
            ii[index[i].n].pri = index[i].pri;
            ii[index[i].n].n = i;
        }

         for (i = Line[ 0 ].b;i <= Line[ 0 ].e;i ++ )
            inser_del(ii[i].n, 1 );

         for (i = 1 ;i < M;i ++ )
        {
            Line[i - 1 ].ans = solve(Line[i - 1 ].k);
             if (Line[i  -   1  ].e >= Line[i].b)
             { for   (j  =  Line[i  -   1  ].b; j  <  Line[i].b; j  ++  )
                inser_del(ii[j].n, - 1 );
              for   (j  =  Line[i  -   1  ].e  +   1  ; j  <=  Line[i].e; j  ++  )
               inser_del(ii[j].n, 1 );
             
            } 
             else  
            {
              for (j = Line[i  -   1 ].b;j <= Line[i  -   1  ].e;j  ++  )
                 inser_del(ii[j].n, - 1 );
              for   (j  =  Line[i].b; j  <=  Line[i].e; j  ++  )
                 inser_del(ii[j].n, 1 );
            }
        }
        Line[i - 1 ].ans = solve(Line[i - 1 ].k);
         for (i = 0 ;i < M;i ++ )
            res[Line[i].n] = Line[i].ans;
         for (i = 0 ;i < M;i ++ )
            printf( " %d\n " ,res[i]);

    return  0 ;
}