LeetCode-in-Java
945. Minimum Increment to Make Array Unique
Medium
You are given an integer array nums. In one move, you can pick an index i where 0 <= i < nums.length and increment nums[i] by 1.
Return the minimum number of moves to make every value in nums unique.
Example 1:
Input: nums = [1,2,2]
Output: 1
Explanation: After 1 move, the array could be [1, 2, 3].
Example 2:
Input: nums = [3,2,1,2,1,7]
Output: 6
Explanation: After 6 moves, the array could be [3, 4, 1, 2, 5, 7]. It can be shown with 5 or less moves that it is impossible for the array to have all unique values.
Constraints:
1 <= nums.length <= 1050 <= nums[i] <= 105
Solution
public class Solution {
public int minIncrementForUnique(int[] nums) {
int max = 0;
for (int num : nums) {
max = Math.max(max, num);
}
int[] counts = new int[nums.length + max];
for (int num : nums) {
counts[num]++;
}
int minMoves = 0;
for (int i = 0; i < counts.length; i++) {
if (counts[i] <= 1) {
continue;
}
int remaining = counts[i] - 1;
minMoves = minMoves + remaining;
counts[i + 1] = counts[i + 1] + remaining;
}
return minMoves;
}
}