【POJ】2503 Babelfish

字典树简单题。

#include <cstdio>
#include <cstring>
#include <cstdlib>

typedef struct Trie {
    Trie *next[26];
    char str[15];
} Trie;

Trie root;

void create(char str[], char des[]) {
    int i = 0, j, id;
    Trie *p = &root, *q;

    while (str[i]) {
        id = str[i] - 'a';
        if (p->next[id] == NULL) {
            q = (Trie *)malloc(sizeof(Trie));
            for (j=0; j<26; ++j)
                q->next[j] = NULL;
            p->next[id] = q;
        }
        p = p->next[id];
        ++i;
    }
    strcpy(p->str, des);
}

void find(char str[]) {
    int i = 0, id;
    Trie *p = &root;

    while (str[i]) {
        id = str[i] - 'a';
        if (p->next[id] == NULL) {
            printf("eh\n");
            return ;
        }
        p = p->next[id];
        ++i;
    }
    printf("%s\n", p->str);
}

void del(Trie *t) {
    int i;
    if (t == NULL)
        return ;
    for (i=0; i<26; ++i)
        del(t->next[i]);
    free(t);
}

int main() {
    char src[12], des[25];
    char *p;

    for (int i=0; i<26; ++i)
        root.next[i] = NULL;

    while (gets(des)!=NULL && des[0]!='\0') {
        p = strchr(des, ' ');
        strcpy(src, p+1);
        *p = '\0';
        create(src, des);
    }

    while (scanf("%s", src) != EOF)
        find(src);

    return 0;
}