🥉

Number Complement

Created

2021/12/27 08:07

문제 번호

476

카테고리

Bit Manipulation

Number Complement - LeetCode

The complement of an integer is the integer you get when you flip all the 0's to 1's and all the 1's to 0's in its binary representation. For example, The integer 5 is "101" in binary and its complement is "010" which is the integer 2.

https://leetcode.com/problems/number-complement/

Code

제출 날짜	시간	메모리
2021/12/27	0 ms	2 MB

// 476. Number Complement
//
// https://leetcode.com/problems/number-complement/

// findComplement function finds the complement number from input number.
// Binary of 5 is 101, and complement of 101 is 010 which is 2.
// To find the complement number, must consider the type size.
// 5 in 64-bit is 0000....101, and its complement is 1111....010 which is not 2.
// The complement number 1111....010 should be masked by 0000...111.
func findComplement(num int) int {
	mask := ^int(0)
	for mask&num > 0 {
		mask <<= 1
	}
	return ^num ^ mask
}
Go
복사