算出下期首尾和值方法

简介：Su Can hesitated for a moment, and then took another look at the wretched senior who didn't look like a good person at all. He thought that the four of them would only cost about forty yuan. If he couldn't pass the social practice class with the stamp he stamped, it would only cost forty yuan. It seems that I will cause trouble for him when the time comes. So he nodded in agreement.