PROGRAM SelectionSortAnimation (input, output);

CONST
   N = 5;

TYPE
   intList = ARRAY [1..N] OF integer;

VAR
   A : intList;
   Index, J, K, Temp : integer;

   PROCEDURE InitArray(VAR iArray: intList; MAXIndex : integer);

   VAR 
     J : integer;

   BEGIN
      FOR J := 1 TO MAXIndex DO
        CASE J OF
           1 : iArray[J] := 6;
           2 : iArray[J] := 4;
           3 : iArray[J] := 8;
           4 : iArray[J] := 10;
           5 : iArray[J] := 1;
        END; { of CASE J }

   END;		{ of PROCEDURE InitArray }

   PROCEDURE DisplayArray(VAR iArray: intList; MAXIndex : integer);

   VAR 
     J : integer;

   BEGIN
      FOR J := 1 TO MAXIndex DO
        BEGIN
          writeln('A[',J,'] = ', iArray[J]);
        END;
      writeln;
   END;		{ of PROCEDURE DisplayArray }

BEGIN
 
  InitArray(A, N);
  writeln;
  writeln('Contents of array A[J] before selection sort: ');
  DisplayArray(A, N);

  FOR J := 1 TO N - 1 DO
    BEGIN
      Index := J;
      FOR K := J + 1 TO N DO
        IF A[K] < A[Index] THEN
          BEGIN
          Index := K; 		{ Find index of smalest number }
          writeln('Decision: A[',K,'] = ',A[K],' < A[',Index,'] = ', A[index]);
          END;
      IF Index <> J THEN
        BEGIN
          writeln('Exchange: A[',Index,'] <==> A[',J,']');
          Temp := A[Index];
          A[Index] := A[J];
          A[J] := Temp;
        END;   { of exchange }
      writeln;
      writeln('Contents of array A[J] after iteratation: ',J);
      DisplayArray(A, N);
    END; { of FOR }

  writeln;
  writeln('Contents of array A[J] after selection sort: ');
  DisplayArray(A, N);

END. { of Main Program SelectionSortAnimation }

{ Expected Results

Contents of array A[J] before selection sort: 
A[1] = 6
A[2] = 4
A[3] = 8
A[4] = 10
A[5] = 1

Decision: A[2] = 4 < A[2] = 4
Decision: A[5] = 1 < A[5] = 1
Exchange: A[5] <==> A[1]

Contents of array A[J] after iteratation: 1
A[1] = 1
A[2] = 4
A[3] = 8
A[4] = 10
A[5] = 6


Contents of array A[J] after iteratation: 2
A[1] = 1
A[2] = 4
A[3] = 8
A[4] = 10
A[5] = 6

Decision: A[5] = 6 < A[5] = 6
Exchange: A[5] <==> A[3]

Contents of array A[J] after iteratation: 3
A[1] = 1
A[2] = 4
A[3] = 6
A[4] = 10
A[5] = 8

Decision: A[5] = 8 < A[5] = 8
Exchange: A[5] <==> A[4]

Contents of array A[J] after iteratation: 4
A[1] = 1
A[2] = 4
A[3] = 6
A[4] = 8
A[5] = 10


Contents of array A[J] after selection sort: 
A[1] = 1
A[2] = 4
A[3] = 6
A[4] = 8
A[5] = 10

}