滑动窗口算法

一、原理

二、实践

2.1、幸运N串

• https://www.nowcoder.com/questionTerminal/3d08b635346d4610b01c6256bc07c394 ```java /**

• 滑动窗口 *

• @return */ public static int sliding_window(String luckCharN) { if (luckCharN == null || luckCharN.length() == 0) {

    return 0;

  } //滑动窗口左右边界 int right = 0; int left = 0; //最长 N字符 int max = 0; //不是 字符N的个数 int notN = 0; char[] chars = luckCharN.toCharArray(); int len = chars.length;

  while (right < len) {

    if (chars[right++] != 'N') {
        //右边界如果不是 N，记录个数
        notN++;
    }
    //个数超过两个
    while (notN > 2) {
        //滑动窗口左边界移动
        if (chars[left++] != 'N') {
            notN--;
        }
    }
    max = Math.max(max, right - left);

  } return max; } ```

参考

• https://www.cnblogs.com/huansky/p/13488234.html