模板：字符串哈希

Posted 2020-12-05 aze-qwq

https://www.luogu.org/problemnew/show/P3370

自然溢出

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 using namespace std;
 6 typedef long long ll;
 7 ll base=19260817;
 8 ll a[10010];
 9 string s;
10 int n, ans=1;
11 ll hashs(string s){
12     int len=s.size();
13     ll ans=0;
14     for (int i=0; i<len; i++)
15         ans=ans*base+(ll)s[i];
16     return ans&0x7fffffff;
17 }
18 int main(){
19     scanf("%d",&n);
20     for (int i=1; i<=n; i++){
21         cin>>s;
22         a[i]=hashs(s);
23     }
24     sort(a+1, a+n+1);
25     for(int i=2; i<=n; i++)
26         if(a[i]!=a[i-1])   ans++;
27     printf("%d
",ans);
28     return 0;
29 }