#include <bits/stdc++.h>
using namespace std;
const long long int mod = 1000000000 + 7;
const long long int N = 1000000 + 6;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long int tc;
  tc = 1;
  while (tc--) {
    long long int n, m;
    cin >> n >> m;
    string s[n];
    for (long long int i = 0; i < n; i++) cin >> s[i];
    long long int d[m];
    for (long long int i = 0; i < m; i++) cin >> d[i];
    long long int ans = 0;
    for (long long int j = 0; j < m; j++) {
      map<char, long long int> p;
      long long int t = 0;
      for (long long int i = 0; i < n; i++) {
        p[s[i][j]]++;
        t = max(t, p[s[i][j]]);
      }
      ans += t * d[j];
    }
    cout << ans;
  }
}
