239876+898764是多少?能脱口而出答案的同学可谓凤毛麟角(学过速算的除外)。我们多数人的第一反应就是求助计算器!假如在你的面前放着一台这样的机子(图1),你就得救了!它可是世界上第一台机械式计算机,解决6位数的整数加减正是它的专利。相对我们现在使用的计算器而言,这台计算机原始落后很多。 239876 + 898764 What is the number of classmates who can blurt out the answer can be described as extremely rare (except learn to speed calculation). The first reaction of most of us is to turn to the calculator! If you put a such a loom in front of you (Figure 1), you’re saved! It’s the world’s first mechanical computer that solves 6-digit Integer addition and subtraction is its patent. This computer lags behind the original calculator we are using.