Given an array A
of 0s and 1s, we may change up to K
values from 0 to 1.
Return the length of the longest (contiguous) subarray that contains only 1s.
Example 1:
Input: A = [1,1,1,0,0,0,1,1,1,1,0], K = 2 Output: 6 Explanation: [1,1,1,0,0,1,1,1,1,1,1] Bolded numbers were flipped from 0 to 1. The longest subarray is underlined.
Example 2:
Input: A = [0,0,1,1,0,0,1,1,1,0,1,1,0,0,0,1,1,1,1], K = 3 Output: 10 Explanation: [0,0,1,1,1,1,1,1,1,1,1,1,0,0,0,1,1,1,1] Bolded numbers were flipped from 0 to 1. The longest subarray is underlined.
Note:
1 <= A.length <= 20000
0 <= K <= A.length
A[i]
is0
or1
Solution : Sliding Window
Maintain a window that has at most K zeros
Time complexity: O(n)
Space complexity: O(1)
C++
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class Solution { public: int longestOnes(vector<int>& A, int K) { int l = 0; int zeros = 0; int ans = 0; for (int r = 0; r < A.size(); ++r) { if (A[r] == 0) ++zeros; while (zeros > K) if (A[l++] == 0) --zeros; ans = max(ans, r - l + 1); } return ans; } }; |