// (a)
if (x > 0)
   y = x - 1;
else
   y = x + 1;

y = (x > 0) ? x-1 : x+1


// (b)
if (x > 0)
   y = x - 1;
else
   z = x + 1;


Can't use conditional expr
Different vars in each branch of if

// (c)
if (x > 0) {
   y = x - 1;  z = x + 1;
} else {
   y = x + 1;  z = x - 1;
}

y = (x > 0) ? x-1 : x+1;
z = (x > 0) ? x+1 : x-1;