import java.util.Arrays;

public class ValidTime {
    private static final String NOT_POSSIBLE = "NOT POSSIBLE";

    public static void main(String[] args) {
        int[] digits1 = new int[]{1, 8, 3, 2, 6, 4};
        int[] digits2 = new int[]{0, 0, 0, 7, 8, 9};
        int[] digits3 = new int[]{2, 4, 5, 9, 5, 9};
        int[] digits4 = new int[]{0, 0, 0, 0, 0, 0};
        System.out.println(solution(digits1));
        System.out.println(solution(digits2));
        System.out.println(solution(digits3));
        System.out.println(solution(digits4));
    }

    public String solution(int A, int B, int C, int D, int E, int F) {
        int[] digits = new int[]{A, B, C, D, E, F};
        return solution(digits);
    }

    public static String solution(int[] digits) {
        Arrays.sort(digits);

        if (isValid(digits)) return toString(digits);

        if (!isHourValid(digits)) return NOT_POSSIBLE;
        if (!isMinuteValid(digits) && !isSecondValid(digits)) return NOT_POSSIBLE;

        if (!isMinuteValid(digits)) {
            swap(digits, 1, 2);
            if (isHourValid(digits) && isMinuteValid(digits)) return toString(digits);
        }
        if (!isSecondValid(digits)) {
            swap(digits, 3, 4);
            if (isSecondValid(digits)) return toString(digits);
        }
        if (!isSecondValid(digits)) {
            swap(digits, 1, 4);
            if (isHourValid(digits) && isSecondValid(digits)) return toString(digits);
        }

        return NOT_POSSIBLE;
    }

    private static boolean isValid(int[] digits) {
        return isHourValid(digits) && isMinuteValid(digits) && isSecondValid(digits);
    }

    private static boolean isHourValid(int[] digits) {
        return (digits[0] <= 1) || (digits[0] == 2 && digits[1] <= 3);
    }

    private static boolean isMinuteValid(int[] digits) {
        return digits[2] <= 5;
    }

    private static boolean isSecondValid(int[] digits) {
        return digits[4] <= 5;
    }

    private static void swap(int[] array, int i, int j) {
        int tmp = array[i];
        array[i] = array[j];
        array[j] = tmp;
    }

    private static String toString(int[] digits) {
        return String.valueOf(digits[0]) + digits[1] + ":" +
                digits[2] + digits[3] + ":" +
                digits[4] + digits[5];
    }
}