### Examples of Conditional Expressions

The following expression determines which variable has the greater value, y or z, and assigns the greater value to the variable x:

    x = (y > z) ? y : z;

The following is an equivalent statement:

    if (y > z)
       x = y;
    else
       x = z;

The following expression calls the function printf, which receives the value of the variable c, if c evaluates to a digit. Otherwise, printf receives the character constant 'x'.

    printf(" c = %c\n", isdigit(c) ? c : 'x');

If the last operand of a conditional expression contains an assignment operator, use parentheses to ensure the expression evaluates properly. For example, the = operator has higher precedence than the ?: operator in the following expression:

    int i,j,k;
    (i == 7) ? j ++ : k = j;

This expression generates an error because it is interpreted as if it were parenthesized this way:

    int i,j,k;
    ((i == 7) ? j ++ : k) = j;

That is, k is treated as the third operand, not the entire assignment expression k = j. The error arises because a conditional expression is not an lvalue, and the assignment is not valid.

To make the expression evaluate correctly, enclose the last operand in parentheses:

    int i,j,k;
    (i == 7) ? j ++ : (k = j);