字典树（入门） 之 hdu 1075

第一次敲字典树还是在去年，就只做了一道，结果今年碰到几个字典树的题，结果都没做掉。

重新再学一遍。。。（这就是去年敲的那道题，又重新敲了一遍）

#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <cstring>
using namespace std;
const int MAX = 26;

struct Trie {
Trie *next[MAX];
char *c;
Trie() {
c = NULL;
memset(next, NULL, sizeof(next));
}
};

Trie *Root = new Trie;

void CreTrie(char *str, char *str1)
{
int len = strlen(str);
Trie *p = Root;
for (int i = 0; i < len; ++i) {
int pos = str[i] - 'a';
if (NULL == p->next[pos]) {
p->next[pos] = new Trie;
}
p = p->next[pos];
}
p->c = new char[10];
strcpy(p->c, str1);
}

char* FinTrie(char *str) {
int len = strlen(str);
Trie *p = Root;
for (int i = 0; i < len; ++i) {
int pos = str[i] - 'a';
if (NULL == p->next[pos]) {
return str;
}
p = p->next[pos];
}
if (p->c != NULL) { return p->c; }
return str;
}

void DelTrie(Trie *T)
{
for (int i = 0; i < MAX; ++i) {
if (T->next[i]) {
DelTrie(T->next[i]);
}
}
delete[] T;
}

bool Judge(char ch)
{
if (ch >= 'a' && ch <= 'z') {
return true;
}
else {
return false;
}
}

int main()
{
//freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);

char str[3000], str1[10], str2[10];
scanf("%s", str1);
while (scanf("%s", str1) && 0 != strcmp(str1, "END")) {
scanf("%s", str2);
CreTrie(str2, str1);
}
scanf("%s", str1);
getchar();
while (gets(str) && 0 != strcmp(str, "END")) {
char word[3000], ans[3000];
memset(word, 0, sizeof(word));
int len = strlen(str);
int w_len = 0;
for (int i = 0; i < len; ++i) {
if (Judge(str[i])) { word[w_len++] = str[i]; }
else {
printf("%s", FinTrie(word));
printf("%c", str[i]);
w_len = 0;
memset(word, 0, sizeof(word));
}
}
printf("\n");
}
DelTrie(Root);
return 0;
}