You are given an integer array nums
(0-indexed). In one operation, you can choose an element of the array and increment it by 1
.
nums = [1,2,3]
, you can choose to increment nums[1]
to make nums = [1,3,3]
.Return the minimum number of operations needed to make nums
strictly increasing.
An array nums
is strictly increasing if nums[i] < nums[i+1]
for all 0 <= i < nums.length - 1
. An array of length 1
is trivially strictly increasing.
Example 1:
Input: nums = [1,1,1] Output: 3 Explanation: You can do the following operations: 1) Increment nums[2], so nums becomes [1,1,2]. 2) Increment nums[1], so nums becomes [1,2,2]. 3) Increment nums[2], so nums becomes [1,2,3].
Example 2:
Input: nums = [1,5,2,4,1] Output: 14
Example 3:
Input: nums = [8] Output: 0
Constraints:
1 <= nums.length <= 5000
1 <= nums[i] <= 104
hmmm不是很懂意义何在,不就是每个元素都比前一个元素+1么?
class Solution {
public int minOperations(int[] nums) {
int result = 0;
int prev = nums[0];
for (int i = 1; i < nums.length; i++) {
if (nums[i] <= prev) {
result += prev + 1 - nums[i];
nums[i] = prev + 1;
}
prev = nums[i];
}
return result;
}
}