Find Nth digit

Find the nth digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...

Note: n is positive and will fit within the range of a 32-bit signed integer (n < 231).


Example 1:

Input:
3

Output:
3

Example 2:

Input:
11

Output:
0

Explanation:
The 11th digit of the sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ... is a 0, which is part of the number 10.

Solution:

def findNthDigit(n):
    digit_len = 1
 while n > digit_len * 9 * (10**(digit_len-1)):
        n-= digit_len * 9 * (10**(digit_len-1))
        digit_len+=1
 
    num = 10 ** (digit_len-1) + (n-1)/digit_len
    nth_digit = num / (10 **((digit_len - 1) - ((n-1)%digit_len)))
    nth_digit = nth_digit%10
 
 return int(nth_digit)

print(findNthDigit(12))
print(findNthDigit(11))
print(findNthDigit(3))


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