Noen enkle nybegynner spørsmål

if(age<20)                //If the age is less than 100
  {
    cout<<"You are pretty young!";    //Just to show it works

  }
    else if(age>20 AND age<50)        //I use else just to show an example
  {
    cout<<"You are old";        //Just to show you it works...
  }
  else if(age>100)        //I use else just to show an example
  {
    cout<<"You are old";        //Just to show you it works...
  }
  else
  {
    cout<<"You are really old";    //Executed if no other statement is executed
  }


hvorfor virker ikke denne:" else if(age>20 AND age<50)"??