HDU 1075 What Are You Talking About Trie题解

翻译火星语，不过火星语也是使用英文单词的，就是把一个单词对应到另外一个单词。

可以使用map， 使用二分，方法很多。

不过最快的应该都是Trie解法了。

把火星语挂在Trie树中，然后在叶子节点增加一个string容器，装英语单词。

查找的时候，找到了出现在Trie中的火星语，就返回string就可以了。

#include <stdio.h>
#include <string>
#include <string.h>
using namespace std;
const int MAX_N = 3001;
const int MAX_WORD = 11;
const int ARR_SIZE = 26;
char gEng[MAX_WORD], gMar[MAX_WORD];
char sentence[MAX_N];

struct Node
{
    string eng;
    Node *arr[ARR_SIZE];
    int n;
    Node():n(0), eng()
    {
        for (int i = 0; i < ARR_SIZE; i++)
        {
            arr[i] = NULL;
        }
    }
};

void delTrie(Node *trie)
{
    if (trie)
    {
        for (int i = 0; i < ARR_SIZE; i++)
        {
            if (trie->arr[i]) delete trie->arr[i], trie->arr[i] = NULL;
        }
        delete trie;
    }
}

Node *Trie;

void insertTrie(char eng[], char mar[])
{
    Node *pCrawl = Trie;
    int len = strlen(mar);
    for (int i = 0; i < len; i++)
    {
        int index = mar[i] - 'a';
        if (!pCrawl->arr[index]) pCrawl->arr[index] = new Node;
        pCrawl = pCrawl->arr[index];
    }
    pCrawl->eng = eng;
    pCrawl->n++;
}

string searchTrie(char mar[])
{
    Node *pCrawl = Trie;
    int len = strlen(mar);
    for (int i = 0; i < len; i++)
    {
        int index = mar[i] - 'a';
        if (!pCrawl->arr[index]) return string();
        pCrawl = pCrawl->arr[index];
    }
    return pCrawl->eng;
}

int main()
{
    Trie = new Node;
    scanf("%s", gEng);
    while (scanf("%s %s", gEng, gMar) && strcmp(gEng, "END"))
    {
        insertTrie(gEng, gMar);
    }
    getchar();    //get rid of '\n'
    
    while (gets(sentence) && strcmp(sentence, "END"))
    {
        int len = strlen(sentence);
        for (int i = 0; i < len; )
        {
            int j = 0;
            for (; i < len && 'a'<=sentence[i] && sentence[i]<='z'; i++)
            {
                gMar[j++] = sentence[i];
            }
            gMar[j] = '\0';//注意字符串后面的'\0'结束符号，否则答案错误

            string str = searchTrie(gMar);
            if (str.empty()) printf("%s", gMar);
            else printf("%s", str.c_str());

            if (i < len) putchar(sentence[i++]);
        }
        putchar('\n');
    }
    delTrie(Trie);
    return 0;
}

HDU 1075 What Are You Talking About Trie题解,布布扣,bubuko.com

HDU 1075 What Are You Talking About Trie题解

原文：http://blog.csdn.net/kenden23/article/details/38365757