PROCEDURE IntToString (x: INTEGER; VAR s: ARRAY OF CHAR): INTEGER;
    VAR j, k: INTEGER; ch: CHAR; a: ARRAY 32 OF CHAR;
  BEGIN
    IF x = 0 THEN s := "0" ELSE
      IF x < 0 THEN s[0] := "-"; k := 1; x := -x ELSE k := 0 END;
      j := 0;
      REPEAT
        a[j] := CHR(x MOD 10 + ORD("0")); x := x DIV 10; INC(j)
      UNTIL x = 0;
      REPEAT DEC(j); ch := a[j]; s[k] := ch; INC(k) UNTIL j = 0;
      s[k] := 0X
    END;
    RETURN k
  END IntToString;