Int g cout inside function g endl int h cout inside

int g()
{
cout << "Inside function g" << endl;
int h()
{
cout << "Inside function h" << endl;
}
}

What is Wrong?
int sum(int x, int y)
{
int result;
result = x + y;
}

What is Wrong?
int sum(int n)
{
if (n == 0)
return 0;
else
n + sum(n-1);
}

What is Wrong?
void f(double a);
{
float a;
cout << a << endl;
}

What is Wrong?
void product()
{
int a, b, c, result;
cout << "Enter 3 integers: ";
cin >> a >> b >> c;
result = a * b * c;
cout << "Result is " << result;
return result;
}