C61 So It Was like This

Xu Haoqing said, "That's right. I first painted it with this bucket of latex paint, and then wrote down the numbers on it with another latex paint that was similar in color. Sure enough, Ma Bentao was able to see the numbers on the wall for a much shorter time than the rest of you."

Li Fengyun, "Tao Zi, how did you do it?"

Tao Zi felt a bit embarrassed. "It's nothing. It's very simple