ENG  RUS Timus Online Judge
Online Judge
Problems
Authors
Online contests
Site news
Webboard
Problem set
Submit solution
Judge status
Guide
Register
Authors ranklist
Current contest
Scheduled contests
Past contests
Rules
back to board

## Discussion of Problem 1423. String Tale

Posted by Maksat "TheBiggestMax" Orazov 2 Apr 2015 10:49
# include <iostream>
# include <fstream>
# include <cmath>
# include <vector>
# include <algorithm>
# include <math.h>
# include <time.h>
# include <string>
# include <string.h>
# include <map>
# include <queue>
# include <stack>

using namespace std;
const int MAXN = 1000000007;//, Maxn = 1000000009;

long long n, a, san, num, dereje = 1, x;

bool zero, one;

string s, h;

int main()
{
cin >> n >> s >> h;

a = n-1;

for (int i=0; i<n; i++) {
san = (san + (dereje * (s[i]-'a'+1))) % MAXN;
num = (num + (dereje * (h[i]-'a'+1))) % MAXN;
dereje = (dereje * 27) % MAXN;
}

if (san == num)    {cout << 0 << '\n'; return 0;}

for (int i=0; i<n; i++) {
san = (san * 27) % MAXN,
san = (san - (((s[a]-'a'+1) * dereje) % MAXN)),
san = (san + MAXN) % MAXN,
san = (san + (s[a]-'a'+1)) % MAXN;

if (san == num)    {cout << i+1 << '\n'; return 0;}
a--;
}

cout << -1 << '\n';

return 0;
}

WA 8.why?
i used HASH!

plz help me!