Microsoft Online Assessment (OA) - Largest K such that both K and -K exist in array

Given an array A of N integers, return the largest integer K > 0 such that both values K and -K exist in the array A. If there is no such integer, the function should return 0.

Example 1:

Input:[3, 2, -2, 5, -3]

Output: 3

Example 2:

Input:[1, 2, 3, -4]

Output: 0

Try it yourself

Implementation

1from typing import List
2
3def largest_k(nums: List[int]) -> int:
4    result = 0
5    for i in nums:
6        if i < 0 and -i in nums:
7            result = max(result, -i)
8    return result
9
10if __name__ == '__main__':
11    nums = [int(x) for x in input().split()]
12    res = largest_k(nums)
13    print(res)
14
1import java.util.Arrays;
2import java.util.HashSet;
3import java.util.List;
4import java.util.Scanner;
5import java.util.stream.Collectors;
6
7class Solution {
8    public static int largestK(List<Integer> nums) {
9        HashSet<Integer> set = new HashSet<>();
10        int curMax = 0;
11        for (int a : nums) {
12            if (set.contains(-a))
13                curMax = Math.max(curMax, Math.abs(a));
14            else
15                set.add(a);
16        }
17        return curMax;
18    }
19
20    public static List<String> splitWords(String s) {
21        return s.isEmpty() ? List.of() : Arrays.asList(s.split(" "));
22    }
23
24    public static void main(String[] args) {
25        Scanner scanner = new Scanner(System.in);
26        List<Integer> nums = splitWords(scanner.nextLine()).stream().map(Integer::parseInt).collect(Collectors.toList());
27        scanner.close();
28        int res = largestK(nums);
29        System.out.println(res);
30    }
31}
32
1function largestK(nums) {
2    let maxValue = 0;
3    const size = nums.length;
4    for (let i = 0; i <= size; i++) {
5        if (Math.abs(nums[i]) > maxValue && nums.indexOf(-nums[i]) !== -1) {
6            maxValue = nums[i];
7        }
8    }
9    return maxValue;
10}
11
12function splitWords(s) {
13    return s == "" ? [] : s.split(' ');
14}
15
16function* main() {
17    const nums = splitWords(yield).map((v) => parseInt(v));
18    const res = largestK(nums);
19    console.log(res);
20}
21
22class EOFError extends Error {}
23{
24    const gen = main();
25    const next = (line) => gen.next(line).done && process.exit();
26    let buf = '';
27    next();
28    process.stdin.setEncoding('utf8');
29    process.stdin.on('data', (data) => {
30        const lines = (buf + data).split('\n');
31        buf = lines.pop();
32        lines.forEach(next);
33    });
34    process.stdin.on('end', () => {
35        buf && next(buf);
36        gen.throw(new EOFError());
37    });
38}
39

Got a question? Ask the Teaching Assistant anything you don't understand.

Still not clear? Ask in the Forum,  Discord or Submit the part you don't understand to our editors.

←
↑TA 👨‍🏫