#nullable enable

#region
var (_input, _iter) = (Array.Empty<string>(), 0);
T I<T>() where T : IParsable<T>
{
    while (_iter >= _input.Length) (_input, _iter) = (Console.ReadLine()!.Trim().Split(' '), 0);
    return T.Parse(_input[_iter++], null);
}
#endregion

var n = I<int>();
var m = I<int>();
var d = new Dictionary<string, int>();
for (var i = 0; i < n; i++) d[I<string>()] = I<int>();
var ans = 0L;
for (var i = 0; i < m; i++) ans += d[I<string>()];
Console.WriteLine(ans);