# Next Greater Element

Posted: 16 Oct, 2020

Difficulty: Moderate

#### You are given an array arr of length N. You have to return a list of integers containing the NGE(next greater element) of each element of the given array. The NGE for an element X is the first greater element on the right side of X in the array. Elements for which no greater element exists, consider the NGE as -1.

#### For Example :

```
If the given array is [1, 3, 2], then you need to return [3, -1, -1]. Because for 1, 3 is the next greater element, for 3 it does not have any greater number to its right, and similarly for 2.
```

##### Input Format :

```
The first line of input contains a single integer T, representing the number of test cases or queries to be run.
Then the T test cases follow.
The first line of each test case contains an integer N, representing the length of the input array(ARR).
The second line contains N single space-separated integers representing elements of the array arr.
```

##### Output Format :

```
For each test case, print a list of integers each representing the NGE(next greater element) of each element of the given array in a single line.
```

##### Note :

```
You are not required to print the expected output, it has already been taken care of. Just implement the function.
```

##### Constraints :

```
1 <= T <= 10
1 <= N <= 10^5
0 <= ARR[i] <= 10^9
Time Limit: 1sec
```

SIMILAR PROBLEMS

Postorder Traversal

Posted: 20 Jan, 2022

Difficulty: Easy

Min Stack

Posted: 22 Jan, 2022

Difficulty: Easy

Stock Span

Posted: 16 Jun, 2022

Difficulty: Moderate

Hills and Soldier

Posted: 7 Jul, 2022

Difficulty: Moderate

Hills and Soldier

Posted: 7 Jul, 2022

Difficulty: Moderate

Next Greater Element II

Posted: 9 Sep, 2022

Difficulty: Moderate