Problem Link

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

How to solve

Complexity Analysis

Time: O(n)

Space: O(1)

Solutions

Python

def missingNumber(self, nums: List[int]) -> int:
    missing = len(nums)

    for i, num in enumerate(nums):
        missing ^= i ^ num

    return missing

Go

func missingNumber(nums []int) int {
    missing := len(nums)

    for i, num := range nums {
        missing ^= i ^ num
    }

    return missing
}

Rust

pub fn missing_number(nums: Vec<i32>) -> i32 {
    let mut missing = nums.len() as i32;

    for (i, &num) in nums.iter().enumerate() {
        missing ^= (i as i32) ^ num;
    }

    missing
}