&&                       Logical AND operator

 exp1 && exp2            Logical AND
 exp1, exp2              any integral expression

    The && operator performs a logical AND on exp1 and exp2; the  resulting
    value is TRUE if both exp1 and exp2 are TRUE; and FALSE otherwise.  The
    operator  evaluates  exp1  first;  if  exp1  is FALSE, then exp2 is not
    evaluated, since the entire expression is already FALSE.  Example:

           if ( (i == j) && (myfunc(k) == 0) )
                       /* if i isn't equal to j, myfunc() isn't called */