hash_wrong

#include "bits/stdc++.h"
using namespace std;

const long long p = 31;
const long long mod = 1e9 + 7;
map<int,set<int>> hs;

long long single_hash (string & s) {
	vector<long long> pows;
	pows.push_back(1);
	int n = (int) s.size();
	for (int i = 0; i < n; ++i) {
		pows.push_back((pows.back() * p) % mod);
	}
	vector<long long> suf_hash,pref_hash;
	pref_hash.push_back(((s[0] - 'a' + 1) * pows[0]) % mod);
	for (int i = 1; i < n; ++i) {
		pref_hash.push_back((pref_hash.back() + (s[i] - 'a' + 1) * pows[i]) % mod);
	}
	suf_hash.push_back(((s[n - 1] - 'a' + 1) * pows[n - 1]) % mod);
	for (int i = n - 2; i >= 0; --i) {
		suf_hash.push_back((suf_hash.back() + (s[i] - 'a' + 1) * pows[i]) % mod);
	}
	cout << pref_hash[n - 1] << ' ' << suf_hash[0] << '\n';
	return pref_hash[n - 1];
}

int main () {
	 ios::sync_with_stdio(false);
	 cin.tie(nullptr);
	 cout.tie(nullptr);
	 string h = "aaaaa";
	 cout << single_hash(h);
	 //~ int T = 1;
	 //~ cin >> T;
	 //~ for (int test_case = 1; test_case <= T; ++test_case) {
		 //~ int n,m;
		 //~ cin >> n >> m;
		 //~ for (int i = 1; i <= n; ++i) {
			 //~ string s;
			 //~ cin >> s;
			 //~ cout << single_hash(s) << '\n';
			 //~ hs[(int) s.size()].insert(single_hash(s));
		 //~ }
		 //~ for (int i = 1; i <= m; ++i) {
			 //~ string s;
			 //~ cin >> s;
			 //~ cout << single_hash(s) << '\n';
		 //~ }
	 //~ }
}