LeetCode-in-Java
1144. Decrease Elements To Make Array Zigzag
Medium
Given an array nums of integers, a move consists of choosing any element and decreasing it by 1.
An array A is a zigzag array if either:
- Every even-indexed element is greater than adjacent elements, ie.
A[0] > A[1] < A[2] > A[3] < A[4] > ... - OR, every odd-indexed element is greater than adjacent elements, ie.
A[0] < A[1] > A[2] < A[3] > A[4] < ...
Return the minimum number of moves to transform the given array nums into a zigzag array.
Example 1:
Input: nums = [1,2,3]
Output: 2
Explanation: We can decrease 2 to 0 or 3 to 1.
Example 2:
Input: nums = [9,6,1,6,2]
Output: 4
Constraints:
1 <= nums.length <= 10001 <= nums[i] <= 1000
Solution
public class Solution {
public int movesToMakeZigzag(int[] nums) {
int ans;
int n = nums.length;
int cur = 0;
if (n == 1) {
return 0;
}
int[] clone = nums.clone();
for (int i = 0; i < n; i += 2) {
if (i == 0) {
if (nums[i] <= nums[i + 1]) {
cur += (nums[i + 1] - nums[i] + 1);
nums[i + 1] = nums[i] - 1;
}
} else if (i == n - 1) {
if (nums[i] <= nums[i - 1]) {
cur += (nums[i - 1] - nums[i] + 1);
}
} else {
if (nums[i] <= nums[i + 1]) {
cur += (nums[i + 1] - nums[i] + 1);
nums[i + 1] = nums[i] - 1;
}
if (nums[i] <= nums[i - 1]) {
cur += (nums[i - 1] - nums[i] + 1);
}
}
}
ans = cur;
cur = 0;
nums = clone;
for (int i = 1; i < n; i += 2) {
if (i != n - 1 && nums[i] <= nums[i + 1]) {
cur += (nums[i + 1] - nums[i] + 1);
nums[i + 1] = nums[i] - 1;
}
if (nums[i] <= nums[i - 1]) {
cur += (nums[i - 1] - nums[i] + 1);
}
}
ans = Math.min(ans, cur);
return ans;
}
}