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# leetcode-1299-easy

Replace Elements with Greatest Element on Right Side

``````Given an array arr, replace every element in that array with the greatest element among the elements to its right, and replace the last element with -1.

After doing so, return the array.

Example 1:

Input: arr = [17,18,5,4,6,1]
Output: [18,6,6,6,1,-1]
Explanation:
- index 0 --> the greatest element to the right of index 0 is index 1 (18).
- index 1 --> the greatest element to the right of index 1 is index 4 (6).
- index 2 --> the greatest element to the right of index 2 is index 4 (6).
- index 3 --> the greatest element to the right of index 3 is index 4 (6).
- index 4 --> the greatest element to the right of index 4 is index 5 (1).
- index 5 --> there are no elements to the right of index 5, so we put -1.
Example 2:

Input: arr = [400]
Output: [-1]
Explanation: There are no elements to the right of index 0.
Constraints:

1 <= arr.length <= 104
1 <= arr[i] <= 105
``````

``````public int[] replaceElements(int[] arr) {
int[] max = new int[arr.length];
max[arr.length - 1] = -1;

int x = arr[arr.length - 1];
for (int i = arr.length - 2; i >= 0; i--) {
if (arr[i] > x) {
max[i] = x;
x = arr[i];
} else {
max[i] = x;
}
}

return max;
}
``````