Given a binary string and a number k, task is to check whether the binary string is evenly divisible by 2k or not.
Input : 11000 k = 2 Output : Yes Explanation : (11000)2 = (24)10 24 is evenly divisible by 2k i.e. 4. Input : 10101 k = 3 Output : No Explanation : (10101)2 = (21)10 21 is not evenly divisible by 2k i.e. 8.
Naive Approach : Compute the binary string into decimal and then simply check whether it is divisible by 2k. But, this approach is not feasible for long binary string as time complexity will be high for computing decimal number from binary string and then dividing it by 2k.
Efficient Approach : In the binary string, check for last k bits. If the all the last k bits are 0, then the binary number is evenly divisible by 2k else it is not evenly divisible. Time complexity using this approach is O(k).
Below is the implementation of the approach.
Time Complexity: O(k)
- Check divisibility in a binary stream
- Python | Check if a given string is binary string or not
- To check divisibility of any large number by 999
- Check if binary string multiple of 3 using DFA
- Check if all the 1's in a binary string are equidistant or not
- Check if a binary string contains consecutive same or not
- Check if a binary string has a 0 between 1s or not | Set 1 (General approach)
- Check if a binary string has two consecutive occurrences of one everywhere
- Check if a binary string contains all permutations of length k
- Check if it is possible to rearrange a binary string with alternate 0s and 1s
- Check if an encoding represents a unique binary string
- Check if a binary string has a 0 between 1s or not | Set 2 (Regular Expression Approach)
- Check whether a binary string can be formed by concatenating given N numbers sequentially
- Longest sub string of 0's in a binary string which is repeated K times
- String slicing in Python to check if a string can become empty by recursive deletion
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