摘要：
UsoperantoUsoperanto is an artificial spoken language designed and regulated by Usoperanto Academy. The academy is now in study to establish Strict Us... 阅读全文
摘要：
frog hasnintegersa1,a2,…,an, and she wants to add them pairwise.Unfortunately, frog is somehow afraid of carries (进位). She defines \emph{hardness}h(x,... 阅读全文