Complete the Recursive base conversion practice problem before reviewing the solution.

Review the Recursive base conversion practice problem with AP CS Tutor Brandon Horn.

## Part (a) `toBinary`

method

```
public static void toBinary(int inBase10)
{
if(inBase10 <= 1)
{
System.out.print(inBase10);
return;
}
toBinary(inBase10 / 2);
System.out.print(inBase10 % 2);
}
```

## Part (b) `toDecimal`

method

```
public static int toDecimal(String inBase2)
{
if(inBase2.length() == 0)
return 0;
int restAsInt = toDecimal(inBase2.substring(1));
if(inBase2.substring(0, 1).equals("0"))
return restAsInt;
else
return (int) (Math.pow(2, inBase2.length() - 1)) + restAsInt;
}
```