Given a non-negative number n. The problem is to toggle the last m bits in the binary representation of n. A toggle operation flips a bit 0 to 1 and a bit 1 to 0.
Constraint: 1 <= m <= n.
Input : n = 21, m = 2 Output : 22 (21)10 = (10101)2 (22)10 = (10110)2 The last two bits in the binary representation of 21 are toggled. Input : n = 107, m = 4 Output : 100
Approach: Following are the steps:
- Calculate num = (1 << m) – 1. This will produce a number num having m number of bits and all will be set.
- Now, perform n = n ^ num. This will toggle the last m bits in n.
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Improved By : nitin mittal