#include <bits/stdc++.h>

#define INF 1e9
#define LINF (1LL << 63 - 1)
#define rep(i,n)for(int i=0;(i)<(int)(n);i++)
#define REP(i,a,b)for(int i=(int)(a);(i)<=(int)(b);i++)
#define ALL(a)  (a).begin(),(a).end()
// #define chmax(a, b) a = max(a, b)
// #define chmin(a, b) a = min(a, b)
#define pb push_back
#define fi first
#define se second
#define sz(x) ((int)x.size())

using namespace std;
//using namespace atcoder;
using ld = long double;
using ll = long long;
using P = pair<ll, ll>;

template<typename T> bool chmin(T& a, const T& b) { if(a > b){ a = b; return 1;} return 0; }
template<typename T> bool chmax(T& a, const T& b) { if(a < b){ a = b; return 1;} return 0; }

const ll ZER = 0;
const ll MOD = 1e9 + 7;


ll dp[202020][10];
int main(){
    // std::cin.tie(0);
    // std::ios::sync_with_stdio(false);

    int n;
    cin >> n;
    vector<ll> a(n);
    rep(i, n){
        cin >> a[i];
        a[i] %= 10;
    }
    dp[0][0] = 1;
    rep(i, n){
        rep(j, 10){
            dp[i + 1][(j + a[i]) % 10] += dp[i][j];
            dp[i + 1][j] += dp[i][j];
        }
    }
    cout << dp[n][0] << endl;
}