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Add C++ solutions for leetcode 1004.

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	`1`	`+#include<vector>`
	`2`	`+#include<algorithm>`
	`3`	`+#include<iostream>`
	`4`	`+using namespace std;`
	`5`	`+`
	`6`	`+class Solution {`
	`7`	`+public:`
	`8`	`+ int longestOnes(vector<int>& nums, int k) {`
	`9`	`+ const int N = nums.size();`
	`10`	`+ int i = 0; // i: 滑动窗口左边界, 固定右边界, 移动左边界`
	`11`	`+ int count = 0; // 已经使用了多少次反转次数`
	`12`	`+ int res = 0; // res: max len`
	`13`	`+ for (int j = 0; j < N; j++)`
	`14`	`+ {`
	`15`	`+ if (nums[j] == 1) // 新加入窗口右侧的数是1, 不需要使用反转次数`
	`16`	`+ res = max(res, j - i + 1);`
	`17`	`+ else {`
	`18`	`+ count++;`
	`19`	`+ while (count > k) // 此时使用的反转次数超了, 需要移动左边界, 直到窗口使用的反转次数减小回到k为止`
	`20`	`+ {`
	`21`	`+ if (nums[i] == 0)`
	`22`	`+ count--;`
	`23`	`+ i++;`
	`24`	`+ }`
	`25`	`+ res = max(res, j - i + 1);`
	`26`	`+ }`
	`27`	`+ }`
	`28`	`+ return res;`
	`29`	`+ }`
	`30`	`+};`
	`31`	`+`
	`32`	`+// Test`
	`33`	`+int main()`
	`34`	`+{`
	`35`	`+ Solution sol;`
	`36`	`+ vector<int> nums = {1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0};`
	`37`	`+ int k = 2;`
	`38`	`+ auto res = sol.longestOnes(nums, k);`
	`39`	`+ cout << res << endl;`
	`40`	`+`
	`41`	`+ return 0;`
	`42`	`+}`

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	`1`	`+#include<vector>`
	`2`	`+#include<algorithm>`
	`3`	`+#include<iostream>`
	`4`	`+using namespace std;`
	`5`	`+`
	`6`	`+class Solution {`
	`7`	`+public:`
	`8`	`+ int longestOnes(vector<int>& nums, int k) {`
	`9`	`+ const int N = nums.size();`
	`10`	`+ int left = 0; // left: 滑动窗口左边界, 固定右边界, 移动左边界`
	`11`	`+ int j = 0; // j: 滑动窗口右边界right`
	`12`	`+ int preSum = 0; // 使用的反转次数 0 -> 1`
	`13`	`+ int res = 0;`
	`14`	`+ for (int j = 0; j < N; j++)`
	`15`	`+ {`
	`16`	`+ preSum += (nums[j] == 0 ? 1 : 0);`
	`17`	`+ if (preSum > k) // 一开始, 让反转次数达到k+1, 然后开始根据情况收缩左边界`
	`18`	`+ {`
	`19`	`+ while (left < j && nums[left] == 1) /* 在左边界每遇到一个1, 就直接移动左边界, 如果遇到1个0, 翻转次数又新腾出了1, 需要先更新preSum的值 */`
	`20`	`+ left++;`
	`21`	`+`
	`22`	`+ preSum -= 1;`
	`23`	`+ left++;`
	`24`	`+ }`
	`25`	`+ res = max(res, j - left + 1); // 此时, 反转次数恰好恢复到k, 可以更新结果了`
	`26`	`+ }`
	`27`	`+ return res;`
	`28`	`+ }`
	`29`	`+};`
	`30`	`+`
	`31`	`+// Test`
	`32`	`+int main()`
	`33`	`+{`
	`34`	`+ Solution sol;`
	`35`	`+ vector<int> nums = {1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0};`
	`36`	`+ int k = 2;`
	`37`	`+ auto res = sol.longestOnes(nums, k);`
	`38`	`+ cout << res << endl;`
	`39`	`+`
	`40`	`+ return 0;`
	`41`	`+}`

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