Temperature Converter; first little project

[Mike1013]

I'm a high school student going into programming classes next year so I wanted to get a hang for C++. I had some prior knowledge of the program but this is my first project. (Not commented I apologize)

#include <iostream>

using namespace std;

int main()
{ int choice, redo;

{if (redo==3);
cout<<"Press 1 if you would like to convert Celsius to Farenheit."<<endl;
cout<<"Press 2 if you would like to convert Farenheit to Celsius: ";
double ctemp, ftemp;
cin>>choice;

if (choice==1)
{cout<<"Enter Celsius temperature: ";
cin>>ctemp;
ftemp=(ctemp*5/9)+32;
cout<<"The Farenheit temperature is: "<<ftemp<<endl;
}

else if (choice==2)
{cout<<"Enter Farenheit temperature: ";
cin>>ftemp;
ctemp=((ftemp-32)*5/9);
cout<<"The Celsius temperature is: "<<ctemp<<endl;
cin.get();
}

cout<<"Would you like to do another conversion? If you do, enter 3: ";
cin>>redo;
}
}

I know this will probably look absolutely horrendous to the trained eye but the program will not loop back to the beginning Press 1/Press 2. I would like assistance on being able to loop the program back to the beginning so another conversion can be done. (Not much experience with the "while" loop function)

[drawingkid1313]

Here ya go:

int choice, redo;
     double ctemp, ftemp;
     while (redo=3)
     {
        cout<<"Press 1 if you would like to convert Celsius to Farenheit."<<endl;
        cout<<"Press 2 if you would like to convert Farenheit to Celsius: ";
        cin>>choice;
     if (choice==1)
     {
                   cout<<"Enter Celsius temperature: ";
                   cin>>ctemp;
                   ftemp=(ctemp*5/9)+32;
                   cout<<"The Farenheit temperature is: "<<ftemp<<endl;
                   }
     else if (choice==2)
     {
          cout<<"Enter Farenheit temperature: ";
          cin>>ftemp;
          ctemp=((ftemp-32)*5/9);
          cout << "The Celsius temperature is: " << ctemp << endl;
          cin.get();
     }
     cout<<"Would you like to do another conversion? If you do, enter 3: ";
     cin>>redo;
     }
     }

I think the mistake you made in the original was putting a ';' after if(redo==3)
I changed that so it uses a while statement, which makes it so that code always runs while redo = 3.
Another useful tip, declare all your variables up top; it makes it a lot easier to keep track of everything once your programs get more advanced and long.

[Mike1013]

Thank you very much for the quick and useful response! :D
It works great now! Just wondering, why does it have to be =3 and not ==3? I apologize for my noobiness.