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1586. Longest Subarray of 1s After Deleting One Element

MediumOpen on LeetCodeProblem statement

Problem Statement

1586. Longest Subarray of 1's After Deleting One Element

Medium

Given a binary array nums, you should delete one element from it.

Return the size of the longest non-empty subarray containing only 1's in the resulting array. Return 0 if there is no such subarray.

 

Example 1:

Input: nums = [1,1,0,1]
Output: 3
Explanation: After deleting the number in position 2, [1,1,1] contains 3 numbers with value of 1's.

Example 2:

Input: nums = [0,1,1,1,0,1,1,0,1]
Output: 5
Explanation: After deleting the number in position 4, [0,1,1,1,1,1,0,1] longest subarray with value of 1's is [1,1,1,1,1].

Example 3:

Input: nums = [1,1,1]
Output: 2
Explanation: You must delete one element.

 

Constraints:

C++

Source file
class Solution {
public:
    int longestSubarray(vector<int>& nums) {
        int maxStreak = 0, currStreak = 0, lastStreak=0;
        for(int i=0; i<nums.size(); i++){   // Modded Sliding Window
            if(!nums[i]){
                maxStreak = max(maxStreak, currStreak+lastStreak);
                lastStreak = currStreak;
                currStreak = 0;
            }
            else currStreak++;
        }
        int ans = max(maxStreak, currStreak+lastStreak); //Last streak might not be flanked by 0 at the end.
        return ans==nums.size()?ans-1:ans;  //Atleast 1 element to be removed
    }
};