hdu1075What Are You Talking About（字典树）

题目链接：hdu1075

/*hdu 1075 What Are You Talking About(字典树)题目大意：    每行输入两个单词，第二个单词可以翻译成第一个单词。给出一串字符，能翻译的输出翻译后的单词，不能的原样输出。思路：字典树*/#include <iostream>#include <cstdio>#include <algorithm>#include <cstring>#include <cmath>#include <cstdlib>using namespace std;bool flag;struct node{    bool flag;    char str[15];    node *next[26];}*root;node *build()//建立结点{    node *p = (node *)malloc(sizeof(node));    for(int i = 0; i < 26; i ++)        p -> next[i] = NULL;    p -> flag = false;    return p;}void save(char *a, char *s){    int len = strlen(s);    node *p;    p = root;    for(int i = 0; i < len; i ++)    {        if(p -> next[s[i] - 'a'] == NULL)            p -> next[s[i] - 'a'] = build();        p = p -> next[s[i] - 'a'];    }    p -> flag = true;//标记，单词的最后一个字符    strcpy(p -> str, a);//在该结点将翻译后的单词存下}void query(char *s){    int len = strlen(s);    node *p;    p = root;    for(int i = 0; i < len; i ++)    {        if(p -> next[s[i] - 'a'] == NULL)        {            printf("%s",s);            return;        }        p = p -> next[s[i] - 'a'];    }    if(p -> flag)//单词能被翻译        printf("%s", p -> str);    else        printf("%s", s);}int main(){   char s1[15],s2[15],ss[3005];   scanf("%s",s1);   root = build();   while(scanf("%s",s1), strcmp(s1, "END"))   {       scanf("%s",s2);       save(s1, s2);   }   scanf("%s",s1);   getchar();   while(gets(ss), strcmp(ss, "END"))   {       int len = strlen(ss);       for(int i = 0; i < len; i ++)       {           if(islower(ss[i]))           {               int j = 0;               memset(s1, '\0', sizeof(s1));               while(islower(ss[i]))                    s1[j++] = ss[i++];               query(s1);           }           if(!islower(ss[i])) printf("%c",ss[i]);       }       if(islower(ss[len-1])) query(s1);       printf("\n");   }   return 0;}