在python列表中查找下一个可用数字

def find_next_available_number(nums):
    nums = sorted(set(nums))  # 去重并排序
    next_num = 1
    for num in nums:
        if num == next_num:
            next_num += 1
        elif num > next_num:
            break
    return next_num

# 示例
nums = [1, 2, 3, 5, 6]
print(find_next_available_number(nums))  # 输出: 4

def find_next_available_number(nums):
    n = len(nums) + 1  # 假设列表是从1开始的连续整数
    expected_sum = n * (n + 1) // 2
    actual_sum = sum(nums)
    return expected_sum - actual_sum

# 示例
nums = [1, 2, 3, 5, 6]
print(find_next_available_number(nums))  # 输出: 4

def find_next_available_number(nums):
    left, right = 0, len(nums)
    while left < right:
        mid = (left + right) // 2
        if nums[mid] == mid + 1:
            left = mid + 1
        else:
            right = mid
    return left + 1

# 示例
nums = [1, 2, 3, 5, 6]
print(find_next_available_number(nums))  # 输出: 4