add

5.leetcode/src/com/fanxb/common/Q142.java

@@ -0,0 +1,62 @@
+package com.fanxb.common;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * 合并两个有序数组
+ * 题目地址：https://leetcode-cn.com/problems/merge-sorted-array/
+ * 解题思路：
+ *
+ * @author fanxb
+ * Date: 2020/6/9 15:10
+ */
+public class Q142 {
+
+    public static class ListNode {
+        int val;
+        ListNode next;
+
+        ListNode(int x) {
+            val = x;
+            next = null;
+        }
+    }
+
+    public static ListNode solution(ListNode head) {
+        Set<ListNode> set = new HashSet<>();
+        while (head != null) {
+            if (set.contains(head)) {
+                return head;
+            } else {
+                set.add(head);
+                head = head.next;
+            }
+        }
+        return null;
+    }
+
+    public static ListNode betterSolution(ListNode head) {
+        ListNode slow = head, fast = head;
+        do {
+            if (fast == null || fast.next == null) {
+                return null;
+            }
+            slow = slow.next;
+            fast = fast.next.next;
+        } while (slow != fast);
+        //此时快慢指针相遇,再加一个指针c
+        ListNode c = head;
+        while (c != slow) {
+            slow = slow.next;
+            c = c.next;
+        }
+        return c;
+    }
+
+
+    public static void main(String[] args) {
+        System.out.println();
+    }
+}

5.leetcode/src/com/fanxb/common/Q167.java

@@ -0,0 +1,36 @@
+package com.fanxb.common;
+
+import java.util.Arrays;
+
+/**
+ * 两数之和 II - 输入有序数组
+ * <p>
+ * 题目地址：https://leetcode-cn.com/problems/two-sum-ii-input-array-is-sorted/
+ * <p>
+ * 解题思路：
+ * 两个指针从两端开始望中间搜索
+ *
+ * @author fanxb
+ * Date: 2020/6/9 15:10
+ */
+public class Q167 {
+
+    public static int[] solution(int[] numbers, int target) {
+        int i = 0, j = numbers.length - 1;
+        int num;
+        while ((num = numbers[i] + numbers[j]) != target) {
+            if (num > target) {
+                j--;
+            } else {
+                i++;
+            }
+        }
+        return new int[]{i+1, j+1};
+    }
+
+
+    public static void main(String[] args) {
+        int[] numbers = {2, 7, 11, 15};
+        System.out.println(Arrays.toString(solution(numbers, 9)));
+    }
+}

5.leetcode/src/com/fanxb/common/Q88.java

@@ -0,0 +1,41 @@
+package com.fanxb.common;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+/**
+ * 合并两个有序数组
+ * 题目地址：https://leetcode-cn.com/problems/merge-sorted-array/
+ * 解题思路：
+ *
+ * @author fanxb
+ * Date: 2020/6/9 15:10
+ */
+public class Q88 {
+
+    public static void solution(int[] nums1, int m, int[] nums2, int n) {
+        int[] res = new int[nums1.length];
+        int i = 0, j = 0;
+        int count = 0;
+        while (count < m + n) {
+            if (i == m) {
+                res[count++] = nums2[j++];
+            } else if (j == n) {
+                res[count++] = nums1[i++];
+            } else if (nums1[i] < nums2[j]) {
+                res[count++] = nums1[i++];
+            } else {
+                res[count++] = nums2[j++];
+            }
+        }
+        System.arraycopy(res, 0, nums1, 0, count);
+    }
+
+
+    public static void main(String[] args) {
+        int[] nums1 = {1, 2, 3, 0, 0, 0};
+        int[] nums2 = {2, 5, 6};
+        solution(nums1, 3, nums2, 3);
+        System.out.println(Arrays.toString(nums1));
+    }
+}