Question

What is the smallest positive integer that can be expressed as the sum of 2021 distinct integers?

Answer 1

Answer:

Given a sorted array (sorted in non-decreasing order) of positive numbers, find the smallest positive integer value that cannot be represented as sum of elements of any subset of given set.

Expected time complexity is O(n).

Examples:

Input: arr[] = {1, 3, 6, 10, 11, 15};

Output: 2

Input: arr[] = {1, 1, 1, 1};

Output: 5

Input: arr[] = {1, 1, 3, 4};

Output: 10

Input: arr[] = {1, 2, 5, 10, 20, 40};

Output: 4

Input: arr[] = {1, 2, 3, 4, 5, 6};

Output: 22