[无讲解] 字符串哈希 模板

版权声明：并没卵用的版权声明~喜欢的就在评论区聊聊天吧~~ https://blog.csdn.net/Frocean/article/details/81773091

存一下自己用的代码

哈希讲解百度上多得是 =-=

题目是洛谷模板 这里采用双哈希 跑了1000ms =-= 懒得优化了

#include <algorithm>
#include <cstring>
#include <cstdio>
#define mod1 2147483647ll
#define mod2 1234567891ll
using namespace std;
typedef unsigned long long ull;
struct answer {
	ull x,y;
} ans[10010];
ull base = 127;
bool cmp(answer a,answer b)
{
	return a.x < b.x;
}
int main()
{
	int n,tot = 1;
	scanf("%d",&n);
	for (int a = 1 ; a <= n ; ++ a)
	{
		char q[1 << 11];
		scanf("%s",q);
			for (int b = 0 ; b < strlen(q) ; ++ b)
			{
				ans[a].x = (ans[a].x * base + (ull)q[b]) % mod1;
				ans[a].y = (ans[a].y * base + (ull)q[b]) % mod2;
			}
	}
	sort(ans + 1,ans + n + 1,cmp);
	for (int a = 1 ; a < n ; ++ a)
	if (ans[a].x != ans[a + 1].x || ans[a].y != ans[a + 1].y) ++tot;
	printf("%d\n",tot);
	return 0;
}