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HDU 1251

代码
#include<iostream>
using namespace std;

const int kind=26;//字母种类

struct Treenode//树的结点结构
{
int count;//这个附加变量在本题中记录遍历到该结点形成的字符串出现的次数,在不同题中可记录不同的内容。
Treenode *next[kind];//指向儿子结点
Treenode()//每个结点的初始化
{
count
=1;
for(int i=0;i<kind;i++)
next[i]
=NULL;
}
};

void insert(Treenode *&root,char *word)//向以root为根结点的树中插入串word
{
Treenode
*location=root;
int i=0,branch=0;

if(location==NULL) {location=new Treenode();root=location;}

while(word[i])
{
branch
=word[i]-'a';
if(location->next[branch]) location->next[branch]->count++;//如果该字符存在,串数量加1
else location->next[branch]=new Treenode();//如果不存在,建新结点
i++;
location
=location->next[branch];
}
}

int search(Treenode *root,char *word)//查找,与插入类似
{
Treenode
*location=root;
int i=0,branch=0,ans;

if(location==NULL) return 0;

while(word[i])
{
branch
=word[i]-'a';
if(!location->next[branch]) return 0;
i
++;
location
=location->next[branch];
ans
=location->count;
}
return ans;
}
int main()
{
char word[10];
char ask[10];
Treenode
*root=NULL;
while(gets(word))
{
if(word[0]=='\0') break;
insert(root,word);
}
while(gets(ask))
cout
<<search(root,ask)<<endl;
return 0;
}

 

posted on 2010-07-21 14:52  keep going  阅读(196)  评论(0编辑  收藏  举报