LeetCode 1679: Max Number of K-Sum Pairs Solution
Master LeetCode problem 1679 (Max Number of K-Sum Pairs), a medium challenge, with our optimized solutions in Java, C++, and Python. Explore detailed explanations, test your code in our interactive editor, and prepare for coding interviews.
1679. Max Number of K-Sum Pairs
Problem Explanation
Explanation
To solve this problem, we can iterate through the array nums and for each element num, we check if k - num exists in a hashmap that stores the frequency of each element we have seen so far. If it exists, we increment the count of pairs found and decrement the frequency of k - num in the hashmap. If it doesn't exist, we increment the frequency of num in the hashmap. We continue this process until we have processed all elements in the array.
Time Complexity
The time complexity of this approach is O(n), where n is the number of elements in the array nums.
Space Complexity
The space complexity is O(n) as well, to store the frequency of elements in the hashmap.
Solution Code
class Solution {
public int maxOperations(int[] nums, int k) {
Map<Integer, Integer> map = new HashMap<>();
int count = 0;
for (int num : nums) {
if (map.containsKey(k - num) && map.get(k - num) > 0) {
count++;
map.put(k - num, map.get(k - num) - 1);
} else {
map.put(num, map.getOrDefault(num, 0) + 1);
}
}
return count;
}
}Try It Yourself
Loading code editor...
Related LeetCode Problems
Frequently Asked Questions
How to solve LeetCode 1679 (Max Number of K-Sum Pairs)?
This page provides optimized solutions for LeetCode problem 1679 (Max Number of K-Sum Pairs) in Java, C++, and Python, along with a detailed explanation and an interactive code editor to test your code.
What is the time complexity of LeetCode 1679 (Max Number of K-Sum Pairs)?
The time complexity for LeetCode 1679 (Max Number of K-Sum Pairs) varies by solution. Check the detailed explanation section for specific complexities in Java, C++, and Python implementations.
Can I run code for LeetCode 1679 on DevExCode?
Yes, DevExCode provides an interactive code editor where you can write, test, and run your code for LeetCode 1679 in Java, C++, or Python.