Run error in first test case

All the test cases were passed successfully except the first one which is showing run error. Please resolve my doubt as I’m to identify the error in my code.
My code is: https://ide.codingblocks.com/s/207184

@devaman1729 hi ,ye apka woh wala test case reh rha hai jab koi bhi odd element na ho linked list me only even ho ,us case ko handle krna hai also vice versa wala case bhi.

Got it! Thank you::blush:

@devaman1729 welcome

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