leetcode

randian666 · randian666 · commit 28fd2f275cba · 2020-05-24T21:47:51.000+08:00
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution.java
@@ -67,8 +67,10 @@ public static ListNode addTwoNumbers(ListNode l1, ListNode l2) {
     public static void main(String[] args) {
         ListNode a=new ListNode(5);
         ListNode b=new ListNode(5);
+        a.next=b;
 
-        ListNode result = addTwoNumbers(a, b);
+
+        ListNode result = addTwoNumbers(a, a);
         for (ListNode node=result;node!=null;node=node.next){
             System.out.println(node.val);
         }
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution11.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution11.java
@@ -33,19 +33,8 @@ public static int removeElement1(int[] nums, int val) {
         }
         return i;
     }
-    public static int removeElement2(int[] nums, int val) {
-        //双指针-覆盖
-        int n=0;
-        for (int i = 0; i < nums.length; i++) {
-            if (nums[n]!=val){
-                nums[n]=nums[i];
-                n++;
-            }
-        }
-        return n;
-    }
     public static void main(String[] args) {
         int[] nums=new int[]{3,2,2,1};
-        System.out.println(removeElement2(nums,2));
+        System.out.println(removeElement1(nums,3));
     }
 }
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution2.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution2.java
@@ -41,7 +41,7 @@ public static int lengthOfLongestSubstring(String s) {
         for(int end=0;end<s.length();end++){
             Character currChar=s.charAt(end);
             if(map.containsKey(currChar)){
-                //移动start
+                //移动start+1
                 start=Math.max(start,map.get(currChar)+1);
             }
             //计算出start和end之间长度
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution3.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution3.java
@@ -58,6 +58,9 @@ public  static int[] topKFrequent(int[] nums, int k) {
     }
 
     public static void main(String[] args) {
-        topKFrequent(new int[]{1,1,3,3,3,3,5},2);
+        int[] ints = topKFrequent(new int[]{1, 1, 3, 3, 3, 3, 5}, 2);
+        for (int anInt : ints) {
+            System.out.println(anInt);
+        }
     }
 }
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution4.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution4.java
@@ -12,6 +12,7 @@
  */
 public class Solution4 {
 
+
     public static String function(int a, int b){
         //存储商和余数
         List<Map<Integer,Integer>> temp=new ArrayList<>();
@@ -23,6 +24,7 @@ public static String function(int a, int b){
             remainder= a%b;
             for (int i=0;i<temp.size();i++){
                 Map<Integer, Integer> integerIntegerMap = temp.get(i);
+                //如果相除得到的整数答案和余数在之前出现过，那么就会开始循环。也就是循环节点
                 if (integerIntegerMap.containsKey(value) && integerIntegerMap.containsValue(remainder)){
                     flag=true;
                     break;
@@ -45,7 +47,7 @@ public static String function(int a, int b){
     }
 
     public static void main(String[] args) {
-        System.out.println(function(1,7));
+        System.out.println(function(3,7));
     }
 
 }
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution8.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution8.java
@@ -31,7 +31,7 @@ public static ListNode removeNthFromEnd(ListNode head, int n) {
         if (head.next==null){
             return null;
         }
-        //增加一个头部节点，方便删除第一个节点。
+        //增加一个头部节点，方便删除倒数的节点刚好是第一个节点。
         ListNode temp=new ListNode(-1);
         temp.next=head;
         ListNode p1=temp;
diff --git a/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution9.java b/src/main/java/com/algorithm/study/demo/algorithm/leetcode/Solution9.java
@@ -43,17 +43,16 @@ public static String longestPalindrome(String s) {
         }
         String res="";
         for (int i=0;i<s.length()-1;i++){
-            //判断aba汇文字符串
+            //判断aba回文字符串 奇数回文
             String p1 = palindrome(s, i, i);
-            //判断aa回文字符串
+            //判断aa回文字符串  偶数回文
             String p2 = palindrome(s, i, i+1);
-            System.out.println(p1);
             res=res.length()>=p1.length()?res:p1;
             res=res.length()>=p2.length()?res:p2;
         }
         return res;
     }
     public static void main(String[] args) {
-        System.out.println(longestPalindrome("abc"));
+        System.out.println(longestPalindrome("babad"));
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -33,19 +33,8 @@ public static int removeElement1(int[] nums, int val) {`
`33`	`33`	`}`
`34`	`34`	`return i;`
`35`	`35`	`}`
`36`		`- public static int removeElement2(int[] nums, int val) {`
`37`		`- //双指针-覆盖`
`38`		`- int n=0;`
`39`		`- for (int i = 0; i < nums.length; i++) {`
`40`		`- if (nums[n]!=val){`
`41`		`- nums[n]=nums[i];`
`42`		`- n++;`
`43`		`- }`
`44`		`- }`
`45`		`- return n;`
`46`		`- }`
`47`	`36`	`public static void main(String[] args) {`
`48`	`37`	`int[] nums=new int[]{3,2,2,1};`
`49`		`- System.out.println(removeElement2(nums,2));`
	`38`	`+ System.out.println(removeElement1(nums,3));`
`50`	`39`	`}`
`51`	`40`	`}`
Original file line number	Diff line number	Diff line change
`@@ -41,7 +41,7 @@ public static int lengthOfLongestSubstring(String s) {`
`41`	`41`	`for(int end=0;end<s.length();end++){`
`42`	`42`	`Character currChar=s.charAt(end);`
`43`	`43`	`if(map.containsKey(currChar)){`
`44`		`- //移动start`
	`44`	`+ //移动start+1`
`45`	`45`	`start=Math.max(start,map.get(currChar)+1);`
`46`	`46`	`}`
`47`	`47`	`//计算出start和end之间长度`
Original file line number	Diff line number	Diff line change
`@@ -58,6 +58,9 @@ public static int[] topKFrequent(int[] nums, int k) {`
`58`	`58`	`}`
`59`	`59`
`60`	`60`	`public static void main(String[] args) {`
`61`		`- topKFrequent(new int[]{1,1,3,3,3,3,5},2);`
	`61`	`+ int[] ints = topKFrequent(new int[]{1, 1, 3, 3, 3, 3, 5}, 2);`
	`62`	`+ for (int anInt : ints) {`
	`63`	`+ System.out.println(anInt);`
	`64`	`+ }`
`62`	`65`	`}`
`63`	`66`	`}`
Original file line number	Diff line number	Diff line change
`@@ -31,7 +31,7 @@ public static ListNode removeNthFromEnd(ListNode head, int n) {`
`31`	`31`	`if (head.next==null){`
`32`	`32`	`return null;`
`33`	`33`	`}`
`34`		`- //增加一个头部节点，方便删除第一个节点。`
	`34`	`+ //增加一个头部节点，方便删除倒数的节点刚好是第一个节点。`
`35`	`35`	`ListNode temp=new ListNode(-1);`
`36`	`36`	`temp.next=head;`
`37`	`37`	`ListNode p1=temp;`
Original file line number	Diff line number	Diff line change
`@@ -43,17 +43,16 @@ public static String longestPalindrome(String s) {`
`43`	`43`	`}`
`44`	`44`	`String res="";`
`45`	`45`	`for (int i=0;i<s.length()-1;i++){`
`46`		`- //判断aba汇文字符串`
	`46`	`+ //判断aba回文字符串奇数回文`
`47`	`47`	`String p1 = palindrome(s, i, i);`
`48`		`- //判断aa回文字符串`
	`48`	`+ //判断aa回文字符串偶数回文`
`49`	`49`	`String p2 = palindrome(s, i, i+1);`
`50`		`- System.out.println(p1);`
`51`	`50`	`res=res.length()>=p1.length()?res:p1;`
`52`	`51`	`res=res.length()>=p2.length()?res:p2;`
`53`	`52`	`}`
`54`	`53`	`return res;`
`55`	`54`	`}`
`56`	`55`	`public static void main(String[] args) {`
`57`		`- System.out.println(longestPalindrome("abc"));`
	`56`	`+ System.out.println(longestPalindrome("babad"));`
`58`	`57`	`}`
`59`	`58`	`}`