leetcode-2160-easy

Minimum Sum of Four Digit Number After Splitting Digits

You are given a positive integer num consisting of exactly four digits. Split num into two new integers new1 and new2 by using the digits found in num. Leading zeros are allowed in new1 and new2, and all the digits found in num must be used.

For example, given num = 2932, you have the following digits: two 2's, one 9 and one 3. Some of the possible pairs [new1, new2] are [22, 93], [23, 92], [223, 9] and [2, 329].
Return the minimum possible sum of new1 and new2.

 

Example 1:

Input: num = 2932
Output: 52
Explanation: Some possible pairs [new1, new2] are [29, 23], [223, 9], etc.
The minimum sum can be obtained by the pair [29, 23]: 29 + 23 = 52.
Example 2:

Input: num = 4009
Output: 13
Explanation: Some possible pairs [new1, new2] are [0, 49], [490, 0], etc. 
The minimum sum can be obtained by the pair [4, 9]: 4 + 9 = 13.

思路一： 四个数字，组成两个数字，所以尽可能把大的数字放进位低，小的数字放进位高

public int minimumSum(int num) {
	int[] arr = new int[4];
	for (int i = 0; i < 4; i++) {
		arr[i] = num % 10;
		num /= 10;
	}

	Arrays.sort(arr);

	return arr[0] * 10 + arr[3] + arr[1] * 10 + arr[2];
}