Unreachable code in function main()! cannot make it work!

[DavidSS]

I just started programming, and I followed a tutorial to make a calculator. Once I was done, I wanted to make it more advanced, so it wouldn't crash if I try to divide by 0, but instead not giving me the choice of dividing. I thought I was done, but then it simply just skipped the part where it actually shows the result. I tried to fix it, but now I get the calculator.cpp 58: Unreachable code in function main() error.
This is my code. Anyone who can solve the problem? Okay, it seems it works anyway, the warning message is just displayed when I compile, but does not stop me from compiling or running the program.

#include <stdio.h>
#include <iostream.h>
 
int main()
{
 
  float num1;
  float num2;
  int num3;
  float num4;
 
  cout << "Enter a number." << endl;
  cin >> num1;
 
  cout << "Enter a second number." << endl;
  cin >> num2;
 
  if (num1 == 0 || num2 == 0)
  {
    {
    cout << "Choose an operation." << endl;
    cout << "Type 1 to add, 2 to subtract or 3 to multiply." << endl;
    cin >> num3;
    }
 
    if (num3 >3 || num3 <1)
    {
      cout << "You operation choice isn't valid! Please run the program again." << endl;
      cout << "Press Enter to end the proogram." << endl;
      getchar();
      return 0;
    }
    else
    {
      if (num3 == 1)
      {
        num4 = num1 +  num2;
        cout << "Result is: "<< num4<< endl;
      }
      else if (num3 == 2)
      {
        num4 = num1 - num2;
        cout << "Result is: "<< num4<< endl;
      }
      else if (num3 == 3)
      {
        num4 = num1 * num2;
        cout << "Result is: "<< num4<< endl;
      }
 
    }
  }
 
  cout << "Press Enter to end the program." << endl;
  getchar();
  return 0;
 
  if (num1 != 0 || num2 !=0)
  {
    {
    cout << "Choose an operation." << endl;
    cout << "Type 1 to add, 2 to subtract, 3 to multiply or 4 to divide." << endl;
    cin >> num3;
    }
 
    if (num3 >4 || num3 <1)
    {
      cout << "You operation choice isn't valid! Please run the program again." << endl;
      cout << "Press Enter to end the proogram." << endl;
      getchar();
      return 0;
    }
  }
  else
  {
    if (num3 == 1)
    {
      num4 = num1 +  num2;
      cout << "Result is: "<< num4<< endl;
    }
    else if (num3 == 2)
    {
      num4 = num1 - num2;
      cout << "Result is: "<< num4<< endl;
    }
    else if (num3 == 3)
    {
      num4 = num1 * num2;
      cout << "Result is: "<< num4<< endl;
    }
    else if (num3 == 4)
    {
      num4 = num1 / num2;
      cout << "Result is: "<< num4<< endl;
    }
 
  }
 
  cout << "Press Enter to end the program." << endl;
  getchar();
 
  return 0;
}

[weaknessforcats]

The code is unreachable because you have:

return 0;

on the line above.

There is no way the execution can get past that return.

The warning can be removed just by deleting all the code after that return.