# Minimum Increment To Make Array Unique Problem

## Description

LeetCode Problem 945.

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:

``````1
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Input: nums = [1,2,2]
Output: 1
Explanation: After 1 move, the array could be [1, 2, 3].
``````

Example 2:

``````1
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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 <= 10^5
• 0 <= nums[i] <= 10^5

## Sample C++ Code using Greedy Approach

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class Solution {
public:
int minIncrementForUnique(vector<int>& A) {
sort(A.begin(), A.end());
int maxVal = A.back();
int ans = 0;
for (int i = 1; i < A.size(); i++) {
if (A[i] <= A[i-1]) {
int gap = A[i-1] - A[i] + 1;
ans += gap;
A[i] += gap;
}
}
return ans;
}
};
``````