# 20. Minimum Operations to Reduce X to Zero

The problem can be found at the following link: [Question Link](https://leetcode.com/problems/minimum-operations-to-reduce-x-to-zero/description)

## My Approach

We have to minimixe the left and right element of a array thats meanwe have to maximize the number element of a subarray which present in the array which sum equal to tatolSum-x

To find the max middle subarray element or length

we will use sliding window technique/two pointer approach -

1. Initially we will set left and right pointer at 0 index
2. We will move right pointer until CurrSum > totalSum - x
3. if CurrSum > totalSum - x we will move left pointer and also check the condition that l<=r
4. Update our maxLength if and only if currSum == totalSum - x
5. Repeat the above steps until we reach the end of the array.
6. At last if we did not find any such window we will return -1 as answer

## Time and Auxiliary Space Complexity

* **Time Complexity**: `O(n)`
* **Auxiliary Space Complexity**: `O(1)`

## Code (C++)

```cpp

class Solution {
public:
    int minOperations(vector<int>& nums, int x) {
        int n = nums.size();

        int sum =0;
        for(int i:nums) sum += i;

        int i=0;
        int maxlen = INT_MIN, currsum=0;
        int target = sum -x;
        bool found = false;
        for(int j=0;j<n;j++){
            currsum += nums[j];

            while(i<=j && currsum>target){
                currsum -= nums[i];
                i++;
            }
            if(currsum == target){
                found = true;
                maxlen = max(maxlen, j-i+1);
            }
        }

        return found? n-maxlen: -1;

    }
};

```

## Contribution and Support

For discussions, questions, or doubts related to this solution, please visit our [discussion section](https://leetcode.com/discuss/general-discussion). We welcome your input and aim to foster a collaborative learning environment.

If you find this solution helpful, consider supporting us by giving a `⭐ star` to the [rishabhv12/Daily-Leetcode-Solution](https://github.com/rishabhv12/Daily-Leetcode-Solution) repository.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://code-render.gitbook.io/leetcode-editorials/09-september/20-minimum-operations-to-reduce-x-to-zero.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.