Create C8GetMaxLength.md

CodingInterviewGuide/C8GetMaxLength.md

@@ -0,0 +1,47 @@
+```
+package Chapter8;
+
+/**
+ * @author Ethan
+ * @desc 未排序正数数组累加和满足给定值的最大子数组的长度
+ */
+public class C8GetMaxLength {
+
+	/**
+	 * @author Ethan
+	 * @desc  基于left和right滑动的方法
+	 */
+	public int getMaxLength(int[] arr,int k){
+		//1-异常参数检测
+		if(arr == null || arr.length == 0){
+			return 0;
+		}
+		//2-初始化
+		int left = 0;
+		int right = 0;
+		int sum = arr[0];
+		int arrLen = arr.length;
+		int len = 0;
+		
+		//3-left和right移动
+		while(right < arrLen){
+			if(sum == k){
+				//更新最大值
+				len = Math.max(len,right - left + 1);
+				//left右移
+				sum -= arr[left++];
+			}else if(sum < k){
+				right++;
+				//此处无判断，会抛出NullPointerException
+				if(right == arrLen){
+					break;
+				}
+				sum += arr[right];
+			}else{
+				sum -= arr[left++];
+			}
+		}
+		return len;
+	}
+}
+```