POJ 2503 Babelfish

解题思路:字典树

#include <iostream>
using namespace std;
#define MAXN 1000001
char dic[MAXN],word[MAXN][11],ch[11];
int size,first[MAXN],next[MAXN],place[MAXN];

void Build(int n)
{
    int i,t,p=0,l=strlen(ch);
    for(i = 0; i<l;i++)
    {
        t=first[p];
        while (t&&dic[t]!=ch[i])t=next[t];
        if(!t)
        {
            dic[++size]=ch[i],next[size]=first[p];
            first[p]=size,first[size]=0,p=size;
        }
        else
            p=t;
    }
    place[p]=n;
}
int main()
{
    int i,t,p,l,n,size=n=0;
    char str[30];
    while (gets(str)&&str[0]!='\0')
        sscanf(str, "%s %s",word[++n], ch),Build(n);
    while (gets(ch)&&ch[0]!='\0')
    {
        p=0,l=strlen(ch);
        for(i=0;i<l;i++){t=first[p];while (t&&dic[t]!=ch[i])t=next[t];p=t;}
        (p==0)?printf("eh\n"):printf("%s\n",word[place[p]]);
    }
    return 0;
}