# Conditional Expressions.

We have a short-hand construct for some if ... else ... constructs.

Consider the following two examples.

Example 1 | Example 2
--- | ---

      if ( x == 1 )
        y = 10;
      else
        y = 20;

      y = (x == 1) ? 10 : 20;

These examples both perform the same function. If x is 1 then y becomes 10 else y becomes 20. The example on the right evaluates the first expression '(x ==1 )' and if true evaluates the second '10'. If false the third is evaluated. Here is another example.

Example 1 | Example 2
--- | ---

     if ( x == 1 )
       puts("take car");
     else
       puts("take bike");

     (x == 1) ? puts("take car") : puts("take bike");

        or

     puts( (x == 1) ? "take car" : "take bike");

It has been said that the compiler can create more efficent code from a conditional expression possibly at the expence of readable code. Unless you are writing time critical code (and lets face it, thats unlikely) the more efficent code is not much of a reason to use this construct. I feel that it has its uses, but should not be lost into some complex statement, but, since when did C programmers worry if anyone else could read their code ;-)

## See also:

- if keyword.
- switch keyword.
- A use within printf..

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