<gh_stars>0
# @l2g 268 python3
# [268] Missing Number
# Difficulty: Easy
# https://leetcode.com/problems/missing-number
#
# Given an array nums containing n distinct numbers in the range [0,n],
# return the only number in the range that is missing from the array.
# Follow up: Could you implement a solution using only O(1) extra space complexity and O(n) runtime complexity?
#
# Example 1:
#
# Input: nums = [3,0,1]
# Output: 2
# Explanation: n = 3 since there are 3 numbers,so all numbers are in the range [0,3].
# 2 is the missing number in the range since it does not appear in nums.
#
# Example 2:
#
# Input: nums = [0,1]
# Output: 2
# Explanation: n = 2 since there are 2 numbers,so all numbers are in the range [0,2].
# 2 is the missing number in the range since it does not appear in nums.
#
# Example 3:
#
# Input: nums = [9,6,4,2,3,5,7,0,1]
# Output: 8
# Explanation: n = 9 since there are 9 numbers,so all numbers are in the range [0,9].
# 8 is the missing number in the range since it does not appear in nums.
#
# Example 4:
#
# Input: nums = [0]
# Output: 1
# Explanation: n = 1 since there is 1 number,so all numbers are in the range [0,1].
# 1 is the missing number in the range since it does not appear in nums.
#
#
# Constraints:
#
# n == nums.length
# 1 <= n <= 10^4
# 0 <= nums[i] <= n
# All the numbers of nums are unique.
#
#

from typing import List


class Solution:
    def missingNumber(self, nums: List[int]) -> int:
        n = len(nums)
        return n * (n + 1) // 2 - sum(nums)


if __name__ == "__main__":
    import os

    import pytest

    pytest.main([os.path.join("tests", "test_268.py")])

# @l2g 268 python3
# [268] Missing Number
# Difficulty: Easy
# https://leetcode.com/problems/missing-number
#
# Given an array nums containing n distinct numbers in the range [0,n],
# return the only number in the range that is missing from the array.
# Follow up: Could you implement a solution using only O(1) extra space complexity and O(n) runtime complexity?
#
# Example 1:
#
# Input: nums = [3,0,1]
# Output: 2
# Explanation: n = 3 since there are 3 numbers,so all numbers are in the range [0,3].
# 2 is the missing number in the range since it does not appear in nums.
#
# Example 2:
#
# Input: nums = [0,1]
# Output: 2
# Explanation: n = 2 since there are 2 numbers,so all numbers are in the range [0,2].
# 2 is the missing number in the range since it does not appear in nums.
#
# Example 3:
#
# Input: nums = [9,6,4,2,3,5,7,0,1]
# Output: 8
# Explanation: n = 9 since there are 9 numbers,so all numbers are in the range [0,9].
# 8 is the missing number in the range since it does not appear in nums.
#
# Example 4:
#
# Input: nums = [0]
# Output: 1
# Explanation: n = 1 since there is 1 number,so all numbers are in the range [0,1].
# 1 is the missing number in the range since it does not appear in nums.
#
#
# Constraints:
#
# n == nums.length
# 1 <= n <= 10^4
# 0 <= nums[i] <= n
# All the numbers of nums are unique.
#
#

from typing import List


class Solution:
    def missingNumber(self, nums: List[int]) -> int:
        n = len(nums)
        return n * (n + 1) // 2 - sum(nums)


if __name__ == "__main__":
    import os

    import pytest

    pytest.main([os.path.join("tests", "test_268.py")])
# @l2g 268 python3 # [268] Missing Number # Difficulty: Easy # https://leetcode.com/problems/missing-number # # Given an array nums containing n distinct numbers in the range [0,n], # return the only number in the range that is missing from the array. # Follow up: Could you implement a solution using only O(1) extra space complexity and O(n) runtime complexity? # # Example 1: # # Input: nums = [3,0,1] # Output: 2 # Explanation: n = 3 since there are 3 numbers,so all numbers are in the range [0,3]. # 2 is the missing number in the range since it does not appear in nums. # # Example 2: # # Input: nums = [0,1] # Output: 2 # Explanation: n = 2 since there are 2 numbers,so all numbers are in the range [0,2]. # 2 is the missing number in the range since it does not appear in nums. # # Example 3: # # Input: nums = [9,6,4,2,3,5,7,0,1] # Output: 8 # Explanation: n = 9 since there are 9 numbers,so all numbers are in the range [0,9]. # 8 is the missing number in the range since it does not appear in nums. # # Example 4: # # Input: nums = [0] # Output: 1 # Explanation: n = 1 since there is 1 number,so all numbers are in the range [0,1]. # 1 is the missing number in the range since it does not appear in nums. # # # Constraints: # # n == nums.length # 1 <= n <= 10^4 # 0 <= nums[i] <= n # All the numbers of nums are unique. # #