base取个131,13331……都可以
unsigned long long自然取模的话容易被卡
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
#define LL long long
#define ULL unsigned long long
ULL H[100000];
ULL base=13331;
inline ULL Hash(char *s)
{
ULL h=0;
int len=strlen(s);
for(int i=0;i<len;i++)
{
h=h*base+s[i]-'0';
}
return h;
}
int main()
{
int n;
cin>>n;
char s[2000];
for(int i=1;i<=n;i++)
{
scanf("%s",s);
H[i]=Hash(s);
}
sort(H+1,H+n+1);
int m=unique(H+1,H+n+1)-H-1;
printf("%d\n",m);
return 0;
}