Python/project_euler/problem_063/sol1.py
Dhruv 44254cf112
Rename Project Euler directories and other dependent changes (#3300)
* Rename all Project Euler directories:

Reason:
The change was done to maintain consistency throughout the directory
and to keep all directories in sorted order.

Due to the above change, some config files had to be modified:
'problem_22` -> `problem_022`

* Update scripts to pad zeroes in PE directories
2020-10-15 12:43:28 +05:30

35 lines
913 B
Python

"""
The 5-digit number, 16807=75, is also a fifth power. Similarly, the 9-digit number,
134217728=89, is a ninth power.
How many n-digit positive integers exist which are also an nth power?
"""
"""
The maximum base can be 9 because all n-digit numbers < 10^n.
Now 9**23 has 22 digits so the maximum power can be 22.
Using these conclusions, we will calculate the result.
"""
def solution(max_base: int = 10, max_power: int = 22) -> int:
"""
Returns the count of all n-digit numbers which are nth power
>>> solution(10, 22)
49
>>> solution(0, 0)
0
>>> solution(1, 1)
0
>>> solution(-1, -1)
0
"""
bases = range(1, max_base)
powers = range(1, max_power)
return sum(
1 for power in powers for base in bases if len(str((base ** power))) == power
)
if __name__ == "__main__":
print(f"{solution(10, 22) = }")