init

24/01/2497.h

@@ -0,0 +1,35 @@
+//
+// Created by 李洋 on 2024/1/3.
+//
+
+#ifndef LEECODE_C_2497_H
+#define LEECODE_C_2497_H
+
+#include "../../dataStruct/LinkedList/lists.h"
+#include <stack>
+
+using namespace std;
+
+//单调栈
+ListNode *removeNodes(ListNode *head) {
+    stack<ListNode *> S;
+    S.push(head);
+    ListNode *temp = head->next;
+    while (temp) {
+        while (!S.empty() && temp->val > S.top()->val) {
+            S.pop();
+        }
+        S.push(temp);
+        temp = temp->next;
+    }
+    temp = S.top();
+    S.pop();
+    while (!S.empty()) {
+        S.top()->next = temp;
+        temp = S.top();
+        S.pop();
+    }
+    return temp;
+}
+
+#endif //LEECODE_C_2497_H

24/01/670.h

@@ -0,0 +1,33 @@
+//
+// Created by 李洋 on 2024/1/22.
+//
+
+#ifndef LEECODE_C_670_H
+#define LEECODE_C_670_H
+
+#include <string>
+
+using namespace std;
+
+int maximumSwap(int num) {
+    string charArray = to_string(num);
+    int n = charArray.size();
+    int maxIdx = n - 1;
+    int idx1 = -1, idx2 = -1;
+    for (int i = n - 1; i >= 0; i--) {
+        if (charArray[i] > charArray[maxIdx]) {
+            maxIdx = i;
+        } else if (charArray[i] < charArray[maxIdx]) {
+            idx1 = i;
+            idx2 = maxIdx;
+        }
+    }
+    if (idx1 >= 0) {
+        swap(charArray[idx1], charArray[idx2]);
+        return stoi(charArray);
+    } else {
+        return num;
+    }
+}
+
+#endif //LEECODE_C_670_H

24/01/82.h

@@ -0,0 +1,45 @@
+//
+// Created by 李洋 on 2024/1/15.
+//
+
+#ifndef LEECODE_C_82_H
+#define LEECODE_C_82_H
+
+// 本题与83题中要求删除重复多余的节点不同，要求只要重复就删除掉所有重复的节点，关机在于链表头的处理
+// 这里采用的是创建一个新的头节点，然后对后续节点进行继续处理，一次遍历即可
+
+struct ListNode {
+    int val;
+    ListNode *next;
+
+    ListNode() : val(0), next(nullptr) {}
+
+    ListNode(int x) : val(x), next(nullptr) {}
+
+    ListNode(int x, ListNode *next) : val(x), next(next) {}
+};
+
+ListNode *deleteDuplicates(ListNode *head) {
+    if (!head) {
+        return head;
+    }
+
+    ListNode* dummy = new ListNode(0, head);
+
+    ListNode* cur = dummy;
+    while (cur->next && cur->next->next) {
+        if (cur->next->val == cur->next->next->val) {
+            int x = cur->next->val;
+            while (cur->next && cur->next->val == x) {
+                cur->next = cur->next->next;
+            }
+        }
+        else {
+            cur = cur->next;
+        }
+    }
+
+    return dummy->next;
+}
+
+#endif //LEECODE_C_82_H