Grids & Bubbles
Logic
Level
2
The above is a table, where each cell consists of a distinct digit from 1 to 9 with 7 in the center.
The circular bubbles on the borderlines indicate the absolute differences between the pair of numbers in the neighboring cells, 8 of which are known and colored yellow, and 4 of which--A, B, C, D--are unknown and colored red.
What is the 4-digit integer
by
Worranat Pakornrat