Mastermind code taking hours to calculate

I'm trying to implement Knuth's Five-guess Mastermind algorithm in my own version of Mastermind, but when running step 6 it takes my code hours to actually run through everything to get the neccesary information. I was wondering if any of you would know a better way to obtain the same results?

Here is my code with relevant classes, step 6 is mainly executed in the method calculateScore().

The following code is the class in which all of the calculation is being done (it exists mainly to do this, except for a few functions which are not called

```
import java.util.ArrayList;
import java.util.Collections;

public class PhaseComputer extends Phase {

private ArrayList possibleCombList = new ArrayList();
private ArrayList combList = new ArrayList();
private ArrayList possibleOutcomes = new ArrayList();

private String combination = "";
private String code = "";

private int totalGuesses = 0;

public PhaseComputer() {
setPossibleCombList();
setOutComeList();
this.guess = new ArrayList<>();
this.exactlyRight = new ArrayList<>();
this.wrongPlace = new ArrayList<>();
}

public void play() {

generateCode();

blackPins = 0;
whitePins = 0;

System.out.println("Guess " + (totalGuesses + 1) + ": " + code + "\n");

checkBlackPins();

if (blackPins == 4) {
this.win = true;
} else {
checkWhitePins();
}

exactlyRight.add(blackPins);
wrongPlace.add(whitePins);
guess.add(code);

}

public void generateCode() { // Generates the next guess.

if (totalGuesses == 0) { // If this is the first turn, put the next guess equal to 'AABB'.
code = "AABB";
}

else if (possibleCombList.size() == 1) { // If there's only one possible combination left;
code = possibleCombList.get(0);
}

else { // If none of the above are true;

Since you said that Step 6 takes a lot of time, and is mainly executed in the calculateScore() method, why don't we simplify it?

public int calculateScore(String solution) { // Calculate the score of 'solution' on every available combination of pins.
    ArrayList minimum = new ArrayList();
    for (Outcome outcome : possibleOutcomes) {
        int min = 0;
        for (String combination : combList) {
            if (!checkIfPossible(solution, combination, outcome)) {
                min++;
            }
        }
        minimum.add(min);
    }

    return  Collections.min(minimum);
}

Here, you calculate min, add it to a List, and then return the minimum in the List.

It can be faster if you have a variable that holds the minimum of mins:

public int calculateScore(String solution) {
    int minimum = Integer.MAX_VALUE;
    for (Outcome outcome : possibleOutcomes) {
        int min = 0;
        for (String combination : combList) {
            if (!checkIfPossible(solution, combination, outcome)) {
                min++;
            }
        }
        if(minimum > min) {
            minimum = min;
        }
    }
    return min;
}

StackExchange Code Review Q#77954, answer score: 3