LeetCode75——Day16

文章目录

• • 一、题目
  • 二、题解

一、题目

1004. Max Consecutive Ones III

Given a binary array nums and an integer k, return the maximum number of consecutive 1's in the array if you can flip at most k 0's.

Example 1:

Input: nums = 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: nums = 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.

Constraints:

1 <= nums.length <= 105

numsi is either 0 or 1.

0 <= k <= nums.length

二、题解

滑动窗口+前缀和

class Solution {
public:
    int longestOnes(vector<int>& nums, int k) {
        int n = nums.size();
        vector<int> P(n + 1);
        for (int i = 1; i <= n; ++i) {
            P[i] = P[i - 1] + (1 - nums[i - 1]);
        }
        int ans = 0;
        for (int right = 0; right < n; ++right) {
            int left = lower_bound(P.begin(), P.end(), P[right + 1] - k) - P.begin();
            ans = max(ans, right - left + 1);
        }
        return ans;
    }
};