题目描述
Amtel has announced that it will release a 128-bit computer chip by 2010, a 256-bit computer by 2020, and so on, continuing its strategy of doubling the word-size every ten years. (Amtel released a 64-bit computer in 2000, a 32-bit computer in 1990, a 16-bit computer in 1980, an 8-bit computer in 1970, and a 4-bit computer, its first, in 1960.)
Amtel will use a new benchmark – the Factstone – to advertise the vastly improved capacity of its new chips. The Factstone rating is defined to be the largest integer n such that n! can be represented as an unsigned integer in a computer word.
Given a year 1960 ≤ y ≤ 2160, what will be the Factstone rating of Amtel's most recently released chip?
There are several test cases. For each test case, there is one line of input containing y. A line containing 0 follows the last test case. For each test case, output a line giving the Factstone rating.
输入
暂无
输出
暂无
样例输入
1960
1981
0
样例输出
3
8
参考代码
#include<stdio.h>
#include<math.h>
int main()
{
int year;
while (scanf("%d", &year), year)
{
int n = (year - 1940) / 10;
double k = pow ( 2, n) * log10(2), sum = 0;
for (int i = 1; ; i++)
{
sum += log10(i);
if (sum > k)
{
printf("%dn", i - 1);
break;
}
}
}
return 0;}
解析
暂无
