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DK大牛最近分遗产,又偷了一个过来,真是好东西!!

算法流程

必须步骤:preprocess

插入:读字符串入a后insert

查找:读字符串入a后find

 

#include < iostream >
using   namespace  std;
struct  node
{
     bool  f;
     int  next[ 26 ];
     void  init(){memset(next, - 1 , sizeof (next));f = 0 ;}
}s[ 200000 ];
int  p;
char  a[ 100 ];
void  preprocess(){s[p = 0 ].init();}
void  insert()
{
     int  index = 0 ;
     for ( int  i = 0 ;a[i];i ++ )
    {
         int  x = a[i] - 'a ' ;
         if (s[index].next[x] ==- 1 )
        {
            s[ ++ p].init();
            s[index].next[x] = p;
        }
        index = s[index].next[x];
    }
    s[index].f = 1 ;
}
bool  find()
{
     int  index = 0 ;
     for ( int  i = 0 ;a[i];i ++ )
    {
         int  x = a[i] - 'a ' ;
         if (s[index].next[x] ==- 1 )  return   0 ;
        index = s[index].next[x];
    }
     return  s[index].f;
}