poj 2503 Babelfish (哈希)

来源：互联网发布：kinetic sand 淘宝编辑：程序博客网时间：2024/06/08 15:17

题意: 给出 (key ，demo)两个字符串，求输入demo的时候，要输出相应的key，如果没有key，就输出"eh";

题解：简单的哈希处理，链表处理冲突

code:

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;const int maxn = 1e6+5;char a[maxn][12], b[maxn][12];bool vis[maxn];struct node{char *s;char *w;node *next;}word[maxn];int getHashKey(char *s){int key=0;while(*s != '\0'){key = (key*131 + (*s)*151)%maxn;s++;}return key%maxn;}void TurnToHash(char *s, char *p){int key = getHashKey(s);if(vis[key]){node *q = new node;q->s = s;q->w = p;q->next=word[key].next;word[key].next = q;} else {word[key].s = s;word[key].w = p;word[key].next = NULL;}vis[key] = 1;}void query(char *c){int key = getHashKey(c);if(!vis[key]) {printf("eh\n");return ;}node *p = &word[key];while(p){if(!strcmp(p->s, c)) {printf("%s\n", p->w);return ;}p=p->next;}printf("eh\n");return ;}int main(){//freopen("in.txt","r",stdin);memset(vis, 0, sizeof(vis));int i=1;while(true){scanf("%s", a[i]);if(getchar()=='\n') break;scanf("%s", b[i]);TurnToHash(b[i], a[i]);i++;}query(a[i]);char t[50];while(~scanf("%s", t)){if(t[0]=='\0') break; query(t);}return 0;}

0 0