Range checks using a switch statement

Question

My teacher has assigned a program to use both if-else statements and switch statements, so we understand how to implement both. The program asked u

Answer 1

You can do something like:

switch ((round)BMI)
{
    case 1: case 2: case 3: .... case 15: case 16: case 17: cout<< "You are underweight " << endl; break;
    case 18: ... case 24: cout << "You are normal" << endl; break;
    case 25: ... case 29: cout << "You are overweight" << endl; break;
    case 30: ... case 34: cout << "You are obese" << endl; break;
    default: cout << "You are gravely overweight" << endl;
}

Also I couldn't help but notice this that since you are using if-else you can avoid the first condition in else-if statements like:

if (BMI < 18.5)
{
    cout << "You are underweight " << endl;
}
else if (BMI < 25.0)
{
    cout << "You are normal" << endl;
}
else if (BMI < 30.0)
{
    cout << "You are overweight" << endl;
}
else if(BMI < 35)
{
    cout << "You are obese" << endl;
}
else
{
    cout << "You are gravely overweight" << endl;
}

Apart from this, both of your implementations look good.