Given a positive integer N, return the number of positive integers less than or equal to N that have at least 1 repeated digit.
Example 1:
Input: 20
Output: 1
Explanation: The only positive number (<= 20) with at least 1 repeated digit is 11.
Example 2:
Input: 100
Output: 10
Explanation: The positive numbers (<= 100) with atleast 1 repeated digit are 11, 22, 33, 44, 55, 66, 77, 88, 99, and 100.
Example 3:
Input: 1000
Output: 262
Note:
1 <= N <= 10^9
class Solution(object):
def numDupDigitsAtMostN(self, N):
"""
:type N: int
:rtype: int
"""
list_n = map(int, str(N + 1))
res = 0
len_n = len(list_n)
def get_cnt(m, n):
if 0 == n:
return 1
return get_cnt(m, n - 1) * (m - n + 1)
for i in range(1, len_n):
res += 9 * get_cnt(9, i - 1)
s = set()
for i, x in enumerate(list_n):
for y in range(0 if i else 1, x):
if y in s:
continue
res += get_cnt(9 - i, len_n - i - 1)
if x in s:
break;
s.add(x)
return N - res
# return get_permutation_cnt(3)
