How hard is LeetCode 2220. Minimum Bit Flips to Convert Number?

LeetCode 2220. Minimum Bit Flips to Convert Number is rated Easy on LeetCode.

What is the time complexity of LeetCode 2220. Minimum Bit Flips to Convert Number?

The Python solution on this page runs in O(\log n), where n is the size of the integers in the problem.

What is the space complexity of LeetCode 2220. Minimum Bit Flips to Convert Number?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 2220. Minimum Bit Flips to Convert Number cover?

LeetCode 2220. Minimum Bit Flips to Convert Number is tagged Bit Manipulation on LeetCode.

Minimum Bit Flips to Convert Number — LeetCode 2220 Python Solution

EasyBit Manipulation

Problem: #2220
Pattern: Bit Manipulation
Reading time: 2 min
Source: leetcode.com

The problem

A bit flip of a number x is choosing a bit in the binary representation of x and flipping it from either 0 to 1 or 1 to 0. For example, for x = 7, the binary representation is 111 and we may choose any bit (including any leading zeros not shown) and flip it.

Example

Input: start = 10, goal = 7
Output: 3
Explanation: The binary representation of 10 and 7 are 1010 and 0111 respectively. We can convert 10 to 7 in 3 steps:

Python solution

Python

class Solution:
    def minBitFlips(self, start: int, goal: int) -> int:
        return (start ^ goal).bit_count()

Complexity

Measure	Complexity
Time	O(\log n), where n is the size of the integers in the problem
Space	O(1) auxiliary

Pattern: Bit Manipulation

Use XOR, masks and the low-bit trick to replace whole data structures with an integer. LeetCode 2220. Minimum Bit Flips to Convert Number is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Bit Manipulation.

The bit manipulation guide has the Python template for the pattern and the 194 LeetCode problems that use it.

Frequently asked questions

How hard is LeetCode 2220. Minimum Bit Flips to Convert Number?: LeetCode 2220. Minimum Bit Flips to Convert Number is rated Easy on LeetCode.
What is the time complexity of LeetCode 2220. Minimum Bit Flips to Convert Number?: The Python solution on this page runs in O(\log n), where n is the size of the integers in the problem.
What is the space complexity of LeetCode 2220. Minimum Bit Flips to Convert Number?: The Python solution on this page uses O(1) auxiliary space.
What topics does LeetCode 2220. Minimum Bit Flips to Convert Number cover?: LeetCode 2220. Minimum Bit Flips to Convert Number is tagged Bit Manipulation on LeetCode.