【模板】Hash

 1 #include<cstdio>
 2 #include<map>
 3 #include<string>
 4 using namespace std;
 5 map<int, int> dic;
 6 int ans=0,n;
 7 int main() {
 8     scanf("%d\n",&n);
 9     for (int i=1;i<=n;i++) {
10         char c=getchar();
11         int x=0;
12         while (c!=‘\n‘){
13             x=x*2333+c-‘a‘;
14             c=getchar();
15         }
16         if (!dic.count(x)) {
17             ans++;
18             dic[x]=i;
19         }
20     }
21     printf("%d",ans);
22     return 0;
23 }