public CharacterCountMap Subtract(string word)
{
var that = new CharacterCountMap(this);
foreach (var c in word)
{
if (!that.ContainsKey(c) || that[c] == 0)
{
return(null);
}
that[c]--;
}
return(that);
}
public bool AreEqual(CharacterCountMap that)
{
if (this.Keys.Count != that.Keys.Count)
{
return(false);
}
foreach (var k in this.Keys)
{
if (!that.ContainsKey(k))
{
return(false);
}
if (this[k] != that[k])
{
return(false);
}
}
return(true);
}
