An integer is said to be self-descriptive if it has the property that, when digit positions are labeled 0 to N-1, the digit in each position is equal to the number of times that this digit appears in the number. Write a function that will check whether a given positive integer is self-descriptive.
Example 1:
Input: 2020
Output: true
Explanation:
Position 0 has value 2 and there are two 0s in the number
Position 1 has value 0 and there are no 1s in the number
Position 2 has value 2 and there are two 2s
Position 3 has value 0 and there are zero 3sExample 2:
Input: 3211000
Output: true
Explanation:
Position 0 has value 3 and there are three 0s in the number
Position 1 has value 2 and there are two 1s in the number
Position 2 has value 1 and there is one 2 in the number
Position 3 has value 1 and there is one 3 in the number
Position 4 has value 0 and there are zero 4s
Position 5 has value 0 and there are zero 5s
Position 6 has value 0 and there are zero 6sFollow-up:
Generate all self-descriptive numbers that will fit in a 32-bit integer. There are 6 such integers:
1210
2020
21200
3211000
42101000
521001000Comments (23)