Always use a block for if and else cases and while statements.

Do

if (value)
{
    aStatement ();
}
else
{
    anotherStatement ();
}

while (stay_in_loop)
{
    doLoopStatement ();
    ...
}

Don't

if (value)
aStatement ();else anotherStatement ();

while (stay_in_loop)
doLoopStatement ();