What should be the if condition in the following code snippet so that output would be “HelloWorld”.

1. Using printf() function

To print “HelloWorld” using the given code snippet, we need to find a condition that is always false and prints “Hello”, so that the else branch is executed. One possible condition is !printf("Hello"), which is false because the printf() function returns the number of characters it has printed, which is a positive value. For example:

 
We can also use the comma operator instead of depending upon the return value of printf to know what the conditional clause does.

2. Recursive main() function

Another option is to use recursion to solve this problem. We can print the desired output using a static variable with the recursive main() function. The idea is to use a static variable in such a way that the if block is executed in the initial call to the main() function and the else block is executed in the second call to the main() function. Here is an example:

 
Note that we can also use a write custom function instead of calling main() recursively: