简单的数学题
题目描述
就是一道简单的数学题！！！！！
编写程序计算：1-2/3!+3/5!-4/7!+5/9!-6/11!+.....的和
什么时候停止呢？
当某一项的绝对值小于10的-n次方时停止计算。（小于10的-n次方的这一项不用算到和里面）
输入格式
输入只有一行，n
输出格式
结果保留两位小数即可
样例 #1
样例输入 #1
1
样例输出 #1
0.67
提示
注意思维哦
1=

Input Description Placed at here, we recommended that please do not use PRE label since it was did by OJ's problem display system.

Output Description Placed at here, we recommended that please do not use PRE label since it was did by OJ's problem display system.

1

0.67