Java Easy Solution
IntuitionApproachComplexity
Time complexity:

Space complexity:
Code
# Intuition
<!-- Describe your first thoughts on how to solve this problem. -->

# Approach
<!-- Describe your approach to solving the problem. -->

# Complexity
- Time complexity:
<!-- Add your time complexity here, e.g. $$O(n)$$ -->

- Space complexity:
<!-- Add your space complexity here, e.g. $$O(n)$$ -->

# Code
```java []
class Solution {
    public int maximumDifference(int[] nums) {
        int b = Integer.MAX_VALUE;
        int maxDiff = -1;

        for(int i = 0; i<nums.length; i++){
            if(b < nums[i]){
                int p = nums[i] - b;
                maxDiff = Math.max(maxDiff, p);
            }
            else{
                b = nums[i];
            }
        }
        return maxDiff;
    }
}
```
['Java']