I think I figured it out, the problem is your code prints 38644509816278 instead of 38653099750870 for the input in test case 19. I did my best to help based on the context and explanation in your post, hopefully you can take it from here.

To maybe get more helpful feedback, try to update your post with what you think the problem is asking for and also what your code is doing. That helps us help you to debug.

It's simply due to integer overflow instead of just storing ans as long long you should store all variables as long long. AC Submission:85585496

But after spending my 5 minutes on this I'm beginning to think I have too much free time :(