LeetCode-in-Java

2165. Smallest Value of the Rearranged Number

Medium

You are given an integer num. Rearrange the digits of num such that its value is minimized and it does not contain any leading zeros.

Return the rearranged number with minimal value.

Note that the sign of the number does not change after rearranging the digits.

Example 1:

Input: num = 310

Output: 103

Explanation: The possible arrangements for the digits of 310 are 013, 031, 103, 130, 301, 310.

The arrangement with the smallest value that does not contain any leading zeros is 103.

Example 2:

Input: num = -7605

Output: -7650

Explanation: Some possible arrangements for the digits of -7605 are -7650, -6705, -5076, -0567.

The arrangement with the smallest value that does not contain any leading zeros is -7650.

Constraints:

Solution

public class Solution {
    public long smallestNumber(long num) {
        int[] count = new int[10];
        long tempNum;
        if (num > 0) {
            tempNum = num;
        } else {
            tempNum = num * -1;
        }
        int min = 10;
        while (tempNum > 0) {
            int rem = (int) (tempNum % 10);
            if (rem != 0) {
                min = Math.min(min, rem);
            }
            count[rem]++;
            tempNum = tempNum / 10;
        }
        long output = 0;
        if (num > 0) {
            output = output * 10 + min;
            count[min]--;
            for (int i = 0; i < 10; i++) {
                for (int j = 0; j < count[i]; j++) {
                    output = output * 10 + i;
                }
            }
        } else {
            for (int i = 9; i >= 0; i--) {
                for (int j = 0; j < count[i]; j++) {
                    output = output * 10 + i;
                }
            }
            output = output * -1;
        }
        return output;
    }
}