Given two numbers ‘a’ and b’. Write a program to count number of bits needed to be flipped to convert ‘a’ to ‘b’.
Input : a = 10, b = 20 Output : 4 Binary representation of a is 00001010 Binary representation of b is 00010100 We need to flip highlighted four bits in a to make it b. Input : a = 7, b = 10 Output : 3 Binary representation of a is 00000111 Binary representation of b is 00001010 We need to flip highlighted three bits in a to make it b.
1. Calculate XOR of A and B. a_xor_b = A ^ B 2. Count the set bits in the above calculated XOR result. countSetBits(a_xor_b)
XOR of two number will have set bits only at those places where A differs from B.
Thanks to Sahil Rajput for providing above implementation.
To get the set bit count please see this post: Count set bits in an integer
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Improved By : Mithun Kumar