What should be passed into if() to print 'Hello World'?

Question

What should be passed into the if() to print the output as "Hello World"? [Note: It should execute the else block.]

if(?){

} else {
   echo "World";
}

Answer 1

I needs to evaluate to false, and print "Hello" at the same time. printf returns the length of outputted string upon success which is evaluated to true when read in a Boolean context. So reversing that will evaluate to false, executing the else block.

if(!printf("Hello ")){

} else {
   echo "World";
}

Answer 2

!printf("Hello ")

By default, printf in 'C' returns true.