⚡ TL;DR
Solve Maximum Subarray in Dart with working code. Kadane's Algorithm (Optimal) approach with O(n) time, plus complexity analysis and interview tips.
Maximum Subarray (#53 — Medium): Given an integer array nums, find the subarray with the largest sum, and return its sum.
Problem Statement
Given an integer array nums, find the subarray with the largest sum, and return its sum.
Example:
Input: nums = [-2,1,-3,4,-1,2,1,-5,4]
Output: 6
Explanation: The subarray [4,-1,2,1] has the sum 6.Approach: Kadane’s Algorithm (Optimal)
Time: O(n) | Space: O(1)
Kadane’s tracks the best sum ending at each index: either start fresh at current element, or extend the previous sum. The answer is the maximum of all these local bests.
int maxSubArray(List<int> nums) {
if (nums.isEmpty) return 0;
int maxSum = nums[0], current = nums[0];
for (int i = 1; i < nums.length; i++) {
current = nums[i] > current + nums[i] ? nums[i] : current + nums[i];
maxSum = maxSum > current ? maxSum : current;
}
return maxSum;
}
void main() {
print(maxSubArray([-2,1,-3,4,-1,2,1,-5,4])); // 6
}Approach: Brute Force
Time: O(n²) | Space: O(1)
Try every starting point and extend it to all possible endings. Too slow for large inputs but simple to verify correctness.
int maxSubArrayBrute(List<int> nums) {
int maxSum = nums[0];
for (int i = 0; i < nums.length; i++) {
int current = 0;
for (int j = i; j < nums.length; j++) {
current += nums[j];
if (current > maxSum) maxSum = current;
}
}
return maxSum;
}Key Takeaways
- Start with the brute-force approach to understand the problem
- Kadane’s Algorithm (Optimal) gives the optimal O(n) solution
- Practice this pattern — it appears frequently in coding interviews
Related Problems
- Maximum Subarray in Python
- Maximum Subarray in Go
- Maximum Subarray in Swift
- Best Time to Buy and Sell Stock in Dart
- Two Sum in Dart
- Remove Duplicates from Sorted Array in Dart
FAQ
What is the best approach to solve Maximum Subarray in Dart?
The recommended approach is Kadane’s Algorithm (Optimal), which runs in O(n) time with O(1) space. The full Dart implementation is shown above.
What is the time complexity of Maximum Subarray in Dart?
Using Kadane’s Algorithm (Optimal), the time complexity is O(n) and the space complexity is O(1).
Happy coding!
