Logarithm of Factorial
EasyP3Coding
Given an integer n, return the natural logarithm of n!, that is ln(n!), rounded to 4 decimal places.
Do not compute n! itself: it overflows long before n = 100. Use ln(a * b) = ln(a) + ln(b).
Example 1
- Input
- n = 1
- Output
- 0
Example 2
- Input
- n = 2
- Output
- 0.6931
Example 3
- Input
- n = 5
- Output
- 4.7875
Constraints
- 1 <= n <= 10^5
Hints
Give it a real attempt first. Run shows which examples fail.
Saved automatically
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