Pro.ID10158 TitleFactorials Title链接http://10.20.2.8/oj/exercise/problem?problem_id=10158 AC54 Submit243 Ratio22.22% 时间&空间限制描述The factorial of an integer N, written N!, is the product of all the integers from 1 through N inclusive. The factorial quickly becomes very large: 13! is too large to store in a 32-bit integer on most computers, and 70! is too large for most floating-point variables. Your task is to find the rightmost non-zero digit of n!. For example, 5! = 1 × 2 × 3 × 4 × 5 = 120, so the rightmost non-zero digit of 5! is 2. Likewise, 7! = 1 × 2 × 3 × 4 × 5 × 6 × 7 = 5040, so the rightmost non-zero digit of 7! is 4. 输入Multiple test cases. For each case, a single positive integer N no larger than 4,220. 输出Description The factorial of an integer N, written N!, is the product of all the integers from 1 through N inclusive. The factorial quickly becomes very large: 13! is too large to store in a 32-bit integer on most computers, and 70! is too large for most floating-point variables. Your task is to find the rightmost non-zero digit of n!. For example, 5! = 1 × 2 × 3 × 4 × 5 = 120, so the rightmost non-zero digit of 5! is 2. Likewise, 7! = 1 × 2 × 3 × 4 × 5 × 6 × 7 = 5040, so the rightmost non-zero digit of 7! is 4. Input Multiple test cases. For each case, a single positive integer N no larger than 4,220. Output For each case, output a single line containing but a single digit: the right most non-zero digit of N ! . Sample Input 7 Sample Output 4 Source 样例输入7 样例输出4 作者 |