Problem Description In many applications very large integers numbers are required. Some of these applications are using keys for secure transmission of data, encryption, etc. In this problem you are given a number, you have to determine the number of digits in the factorial of the number.
Input Input consists of several lines of integer numbers. The first line contains an integer n, which is the number of cases to be tested, followed by n lines, one integer 1 ≤ n ≤ 10[sup]7[/sup] on each line.
Output The output contains the number of digits in the factorial of the integers appearing in the input.
Sample Input2
10
20
Sample Output7
19
Source Asia 2002, Dhaka (Bengal)
题意:求N的阶乘有多少位
注意:求阶乘时注意会溢出,所以用double类型接收
方法:N(!) = N * (N-1) * …* 1 两边同时取对数,即为N(!)位数。
lg(N!) = lg( N * (N-1) * …* 1 ) 拆开
lg(N!) = lg(N) + lg(N-1) + … + lg(1)
应为lg(10)==1;在(0~10)内lg的值为0,所以结果需要+1表示各位