How to print array in return functiuon - c++

Question

As you see in my code, I have to return an array through return function. What necessary thing do I have to change in my code to disable the warning of return type? When I run this code, it gives me a warning. I have to remove this warning:
warning: no return statement in function returning non-void [-Wreturn-type]
#include <bits/stdc++.h>
using namespace std;
int sort(int a[], int n)
{
int zeros = 0;
for (int i = 0; i < n; i++)
{
if (a[i] == 0)
{
zeros++;
}
}
int k = 0;
while (zeros--)
{
a[k++] = 0;
}
while (k < n)
{
a[k++] = 1;
}
}
int main()
{
int n;
cout << "Enter the n value : ";
cin >> n;
int a[n];
cout << "Enter the array elements : ";
for (int i = 0; i < n; i++)
{
cin >> a[i];
}
sort(a, n);
for (int i = 0; i < n; i++)
{
cout << a[i];
}
return 0;
}

Answer 1

int sort(int a[], int n)
Your sort function is declared to return an int, but you didn't return anything. If you don't want to return anything, declare it using void.
Also, VLA is not valid C++. You should use std::vector instead.
So, your code should look like this.
#include <iostream>
#include <vector>
void sort(std::vector<int> &a) // no need for n
{
int zeros = 0;
for (int i = 0; i < a.size(); i++) // use member function size() instead for n
{
if (a[i] == 0)
{
zeros++;
}
}
int k = 0;
while (zeros--)
{
a[k++] = 0;
}
while (k < n)
{
a[k++] = 1;
}
}
int main()
{
int n;
std::cout << "Enter the n value : ";
std::cin >> n;
std::vector<int> a(n);
std::cout << "Enter the array elements : ";
for (int i = 0; i < n; i++)
{
cin >> a[i];
}
sort(a);
for (cons auto &i : a) // range-base for loop, recommend
{
std::cout << a[i];
}
return 0;
}
Note: using namespace std; and #include <bits/stdc++.h> are both bad practice, so avoid using it.