The numbers on the wooden board were "12▍324▍5667▍72▍4868▍6▍5298?"
Dr. Zhang's eyes were fixed tightly on the "6," the one between the fifth and sixth vertical lines!
He knew he had definitely grasped a clue, but he did not know what the clue was.
So, he quickly called over Liu Yi, "Hey, you there... come look at this!"
Liu Yi leaned in... "What's up?"
Dr. Zhang, without blinking, looked at the number "6," and pointed at it as if afraid it would sprout legs and run away, said, "...this number... it's solitary!"
...
...
"Solitary?" Liu Yi repeated with a frown, and almost in the next second, his eyes lit up, "It's a letter...!" he suddenly exclaimed.
Dr. Zhang was startled... "A letter?"
"Yeah... it's a letter!"
Dr. Zhang puzzled, "But, hadn't we already tried that, and there was no pattern at all with the alphabetical order, and no logic in the algorithms either!"
