Help me in solving GS08 problem

My issue

how goes doees compiler know what lettwr is next

My code

# Update the '_' in the code below

A, B = input().split()
C, D, E = input().split()
F, G, H, I = input().split()
print(A, B, C, D, E, F, G, H, I)

Learning course: Solve Programming problems using Python
Problem Link: How to accept string inputs Practice Problem in Solve Programming problems using Python - CodeChef