shell cpp

#include <iostream>
#include<vector>
#include<sstream>

using namespace std;
vector<int> shellSort(vector<int>);
int main()
{

    int n;
    string str;
    vector<int> ints;

    cout<<"Enter the array to be sorted : ";
    cin>>str;

    for (string::iterator it = str.begin(); it != str.end(); ++it) {
        if (*it == ',') {
            *it = ' ';
        }
        else continue;
    }

    stringstream ss(str);

    while(ss >> n){
        ints.push_back(n);
    }

    ints = shellSort(ints);
    cout<<"\nThe Array after sorting is : ";
    for(int i=0; i<ints.size(); i++){
        cout<<ints[i]<<" ";
    }
}

vector<int> shellSort(vector<int> numbers){
        int gap = numbers.size() / 2;

        while (gap > 0){
            // loop till i is in range from gaps to lenght of the list
            for (int i = 0; i < numbers.size(); i++){
                // store the ith element in the temp variable
                int temp = numbers[i];
                int j = i;
                // applying insertion sort on the sublist
                // shifting the elements larger than the ith element to the right
                while(j >= gap && numbers[j - gap] > temp){
                    numbers[j] = numbers[j - gap];
                    j -= gap;
                }
                // puting the element at its correct position
                numbers[j] = temp;
            }
            // reduce gap by it half
            gap = gap/2;
        }
        return numbers;
    }