字典树基础

int  trie[400100][26];
int sum[400100];
int pos=1;
void insert1(char *s)
{
    int root=0;
    for(int i=0;i<strlen(s);i++)
    {   int ch=s[i]-'a';
        if( trie[ root ][ch]==0  )
          {
             memset(trie[pos],0,sizeof(trie[pos]));//用多少初始化多少
             trie[root][ch]=pos++;
          }
        root=trie[root][ch];
    }
    sum[root]=1;
}

int find1(char *s)
{
    int root=0;
    for(int i=0;i<strlen(s);i++)
    {
        int ch=s[i]-'a';
        if( trie[root][ch]==0 )return false;
        root=trie[root][ch];
    }
    return sum[root];

}
int main()
{
    pos=1;
    memset(sum,0,sizeof(sum));
    memset(trie[0],0,sizeof(trie[0]));
    
    
    
    return 0;
}

指针写法

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
char s[11];
int n,m;
bool p;
struct node
{
    int count;
    node * next[26];
}*root;
node * build()
{
    node * k=new(node);
    k->count=0;
    memset(k->next,0,sizeof(k->next));
    return k;
}
void insert()
{
    node * r=root;
    char * word=s;
     while(*word)
    {
        int id=*word-'a';
        if(r->next[id]==NULL) r->next[id]=build();
        r=r->next[id];
        r->count++;
        word++;
    }
}
int search()
{
    node * r=root;
    char * word=s;
    while(*word)
    {
        int id=*word-'a';
        r=r->next[id];
        if(r==NULL) return 0;
        word++;
    }
    return r->count;
}
int main()
{
    root=build();
    scanf("%d",&n);
    for(int i=1;i<=n;i++) 
    {
            cin>>s;
            insert();
    }
    scanf("%d",&m);
    for(int i=1;i<=m;i++)
    {
        cin>>s;
        printf("%d
",search());
    }
}