Python | Check if there are K consecutive 1’s in a binary number

Given K and a binary number, check if there exists k consecutive 1’s in the binary number.


Input : binary number = 101010101111
            k = 4 
Output : yes
Explanation: at the last 4 index there exists
4 consecutive 1's

Input : binary number = 11100000 k=5 
Output : no
Explanation: There is a maximum of 3 consecutive 
1's in the given binary.

Approach: Create a new string with k 1’s. Using if condition check if there is new in s. In python if new in s: checks if there is any existence if new in s, hence returns true if there is else it returns a false.

Below is the Python implementation of the above approach:





# Python program to check if there 
# is k consecutive 1's in a binary number 
# fucntion to check if there are k 
# consecutive 1's 
def check(s,k):
    # form a new string of k 1's 
    new = "1"*
    # if there is k 1's at any position 
    if new in s:
        print "yes" 
        print "no" 
# driver code
s = "10101001111"
k = 4 
check(s, k)



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