poj 2001 Trie树

题意思路简单，直接贴代码

/*
 * poj2001/win.c
 * Created on: 2011-8-18
 * Author    : ben
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

#define MAXN 1005
#define MAXLEN 25

int N;
char strs[MAXN][MAXLEN];

typedef struct Trie {
    int num;
    struct Trie * br[26];
} Trie;

Trie* newTrieNode() {
    int i;
    Trie* node = (Trie *) malloc(sizeof(Trie));
    for (i = 0; i < 26; i++) {
        node->br[i] = NULL;
    }
    node->num = 0;
    return node;
}

void insert(Trie *root, char *str, int len) {
    int i;
    if (len <= 0) {
        root->num = 1;
        return;
    }
    i = (*str) - 'a';
    if (!root->br[i]) {
        root->br[i] = newTrieNode();
    }
    insert(root->br[i], str + 1, len - 1);
}

void count(Trie *root) {
    int i;
    for (i = 0; i < 26; i++) {
        if (root->br[i]) {
            count(root->br[i]);
            root->num += root->br[i]->num;
        }
    }
}

void destroy(Trie *root) {
    int i;
    for (i = 0; i < 26; i++) {
        if (root->br[i] != NULL) {
            destroy(root->br[i]);
        }
    }
    free(root);
}

void putprefix(Trie *root, char *str, int len) {
    int i;
    if(len < 1 || root->num <= 1) {
        return ;
    }
    putchar(*str);
    i = (*str) - 'a';
    putprefix(root->br[i], str + 1, len - 1);
}

void work() {
    Trie *root = newTrieNode();
    int len, i;
    N = 0;
    while (scanf("%s", strs[N]) != EOF) {
        N++;
    }
    for(i = 0; i < N; i++) {
        len = strlen(strs[i]);
        insert(root, strs[i], len);
    }
    count(root);
    for(i = 0; i < N; i++) {
        printf("%s ", strs[i]);
        putprefix(root, strs[i], strlen(strs[i]));
        putchar('\n');
    }
    destroy(root);
}

int main() {
#ifndef ONLINE_JUDGE
    freopen("data.in", "r", stdin);
#endif
    work();
    return 0;
}