why does this program show returned 1 in error

Question

#include<iostream>

using namespace std;

int main()
{
cout << "I love C++" << endl;

return 0;
}

Answer 1

#include<iostream>
using namespace std;

int main() {
cout << "I love C++" << endl;
return 0;
}

//is same as

#include<iostream>
using namespace std;

int main() {
cout << "I love C++" << endl;
return 1;
}

//is same as

#include<iostream>
using namespace std;

int main() {
cout << "I love C++" << endl;
}

Ask your question precisely if any, my friend.

Answer 2

so what should i do then?