I know this is a easy problem but I am not able to return the vector we need to return the list

Given an unsorted array A of size N that contains only non-negative integers, find a continuous sub-array which adds to a given number S

You don’t need to read input or print anything. The task is to complete the function

subarraySum () which takes arr, N and S as input parameters and returns a list containing the starting and ending positions of the first such occurring subarray from the left where sum equals to S. The two indexes in the list should be according to 1-based indexing. If no such subarray is found, return an array consisting only one element that is -1

class Solution

{

public:

//Function to find a continuous sub-array which adds up to a given number.

vector subarraySum(int arr[], int n, int s)

{

// Your code here

int csum=arr[0];

int st=0;

vectorv;

for(int i=1;i<=n;i++)

{

if(i<n)

csum=csum+arr[i];

while(csum>s&& st<i-1)

{

csum = csum - arr[st];

st++;

}

if(csum==s)

{

v.push_back(st);

v.push_back(i-1);

return v;

}

```
}
}
```

};

input- N = 5, S = 12 A[] = {1,2,3,7,5}

Output: 2 4

my output 1 2