Given a number n, our task is to find all 1 to n bit numbers with no consecutive 1s in their binary representation.
Input : n = 4 Output : 1 2 4 5 8 9 10 These are numbers with 1 to 4 bits and no consecutive ones in binary representation. Input : n = 3 Output : 1 2 4 5
1) There will be 2n numbers with number of bits from 1 to n.
2) Iterate through all 2n numbers. For every number check if it contains consecutive set bits or not. To check, we do bit wise and of current number i and left shifted i. If the bitwise and contains a non-zero bit (or its value is non-zero), then given number doesn’t contain consecutive set bits.
Complexity O(2^n) because ‘for’ loop is run 2^n time.
1 2 4 5
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