/*
ID: dalpone1
TASK: Longest_Beautiful_Sequence
LANG: C++
*/
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define pb push_back
#define ll long long
#define nl '\n'
const int N = 100100, K = 21;
int dp[N][K], n, a[N], k[N], ans;
unordered_map<int, int> lastpos, fakepos;
int main() {
// ifstream cin(".in");
// ofstream cout(".out");
ios::sync_with_stdio(0);
cin.tie(0);
cin >> n;
for (int i = 0; i < n; i++)
cin >> a[i];
for (int i = 0; i < n; i++)
cin >> k[i];
for (int i = 0; i < n; i++)
for (int j = 0; j < i; j++) {
ans++;
ans %= 10;
}
cout << ans;
// lastpos[a[0]] = 0;
// // fakepos[~a[0]] = 0;
// for (int i = 1; i < n; i++) {
// int cnt = __builtin_popcount(a[i]);
// for (int j = 0; j < K; j++) {
// if ((a[i] & (1 << j)) == 0) continue;
// if (lastpos.count(a[i] ^ (1 << j)) == 0) continue;
// dp[i][j] = max(dp[i][j], 1 + dp[lastpos[a[i] ^ (1 << j)]][cnt-1]);
// }
// lastpos[a[i]] = i;
// // fakepos[~a[i]] = i;
// }
}
