private int Part1(int[] banks)
{
int cycles = 0;
HashSet <BanksState> statesSeen = new HashSet <BanksState>();
BanksState initialState = new BanksState(banks);
statesSeen.Add(initialState);
while (true)
{
DoRedistribution(banks);
cycles++;
BanksState currentState = new BanksState(banks);
if (statesSeen.Contains(currentState))
{
return(cycles);
}
statesSeen.Add(currentState);
}
}
private int Part2(int[] banks)
{
int cycles = 0;
Dictionary <BanksState, int> statesSeen = new Dictionary <BanksState, int>();
BanksState initialState = new BanksState(banks);
statesSeen.Add(initialState, 0);
while (true)
{
DoRedistribution(banks);
cycles++;
BanksState currentState = new BanksState(banks);
if (statesSeen.Keys.Contains(currentState))
{
return(cycles - statesSeen[currentState]);
}
statesSeen.Add(currentState, cycles);
}
}
public override bool Equals(object obj)
{
// All of this safety checking is overkill for this simple program, but it's
// good practice (and habit!), so I included it.
if (!(obj is BanksState))
{
return(false);
}
BanksState other = (BanksState)obj;
if (other.Values.Length != this.Values.Length)
{
return(false);
}
for (int i = 0; i < this.Values.Length; i++)
{
if (this.Values[i] != other.Values[i])
{
return(false);
}
}
return(true);
}