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.
class Solution {
public int findNthDigit(int n) {
int digit = 1;
long start = 1;
long count = 9;
while(n > count){
n -= count;
++digit;
start *= 10;
count = 9 * digit * start;
}
long num = start + (n - 1) / digit;
return Long.toString(num).charAt((n - 1) % digit) - '0';
}
}