Java written 24-point card game _java

Any 4 1-13 digits, subtraction calculates 24 points.

Implementation principle:

1) permutations and combinations of 4 digits
2 calculate the probability of each permutation combination

Cal24.java

Import Java.util.HashSet;
 
 
Import Java.util.Set;
  public class Cal24 {private static final double precision = 0.00001;
   
 
  private static final int target = 24;
    Public string[] Execute (string[] inputs) {int[] digits = new INT[4];
    for (int i = 0; i < inputs.length i++) {Digits[i] = integer.valueof (inputs[i));
  Return to new String[]{calc (digits)};
    Private String Calc (final int data[]) {final set<string> out = new hashset<string> (); Combination digit = new combination () {@Override protected void handle (int[] result) {final 
        Int[] R = result; Combination oper = new combination () {@Override protected void handle (int[] c) {Double X
            = R[0];
            for (int i = 0; i < r.length-1 i++) {x = Docalculate (x, R[i + 1], c[i]); } if (Math.Abs (Math.Abs (x)-target) < precision | | Math.Abs (Math.Abs (1/x)-TArget) < precision) {StringBuilder SB = new StringBuilder ();
                for (int j = 0; J < R.length; J + +) {sb.append (r[j]);
                if (J!= r.length-1) {sb.append (Getoperation (C[J)));
            } out.add (Sb.tostring ());
        }
             
          }
        };
         
      Oper.combine (New int[]{0, 1, 2, 3}, Data.length-1, true);
     
    }
    };
     
    Digit.combine (data);
    StringBuilder sb = new StringBuilder ();
      for (string string:out) {sb.append (string);
    Sb.append ("\ n");
  return sb.tostring ();
      Private double Docalculate (double x, double y, int operation) {switch (operation) {case 0:
    return x + y;
    Case 1:return XY;
    Case 2:return x * y;
    Case 3:return x/y;
    Default:return 0;
    }} private static String getoperation (int operation) {Switch (operation) {case 0:return "+";
    Case 1:return "-";
    Case 2:return "*";
    Case 3:return "/";
    Default:return "";
  } public static void Main (string[] args) {System.out.println (New Cal24 (). Calc (New Int[]{1, 5, 5, 5})); }
}

Combination.java

Public abstract class Combination {private Boolean repeat;
   
  private int total = 0;
  public void Combine (int data[]) {Combine (data, data.length, false);
  public void Combine (int data[], int count) {combine (data, count, false);
    public void Combine (int data[], int count, Boolean repeat) {this.repeat = repeat;
    int times = Data.length;
    int size = (int) Math.pow (times, Count);
      for (int i = 0; i < size; i++) {int[] result = ToArray (data, I, count);
        if (result!= null) {handle (result);
      Total + +;
    }} private int[] ToArray (int data[], int i, int count) {int [] indices = new Int[count];
    int times = Data.length;
      for (int j = 0; J < Count; J +) {int temp = 0;
        if (i > 0) {temp = I%times;
      i = (i-temp)/times;
    } Indices[j] = temp;
     } if (!repeat) {//remove repetition for (int x = 0; x < count + x + +) {   for (int y = 0; y < count; y++) {if (x!= y) {if (indices[x] = = Indices[y]) return
          Null
    [] [] result = new Int[count];
      for (int x = 0; x < count x + +) {int selected = data[indices[x]];
    RESULT[X] = selected;
  return result;
  public int gettotal () {return total;
} protected abstract void handle (int[] result); }

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