HW2 Publish

2025-10-08 00:01:57 +08:00
commit fd471a68c4
19 changed files with 2357 additions and 0 deletions
--- a/docs/sort.cpp
+++ b/docs/sort.cpp
@@ -0,0 +1,95 @@
+#include <algorithm>
+#include <iostream>
+#include <vector>
+
+// 比較函式：整數由大到小排序
+bool cmpInt(int a, int b) {
+    return a > b;
+}
+
+// 定義學生結構
+struct student {
+    int number; // 學號
+    int score;  // 成績
+};
+
+// 學號升冪排序
+bool cmpStucdentnumberUp(student a, student b) {
+    return a.number < b.number;
+}
+
+// 學號降冪排序
+bool cmpStucdentnumberDown(student a, student b) {
+    return a.number > b.number;
+}
+
+// 成績升冪排序
+bool cmpStucdentScoreUp(student a, student b) {
+    return a.score < b.score;
+}
+
+// 成績降冪排序
+bool cmpStucdentScoreDown(student a, student b) {
+    return a.score > b.score;
+}
+
+int main() {
+    // ----------- int 排序範例 -----------
+
+    // 建立一個整數 vector
+    std::vector<int> nums = {10, 14, 6, 7, 8, 15, 1, 9, 12, 11, 3, 4, 5, 13, 2};
+
+    // 升冪排序 (小到大) - 預設比較器
+    std::sort(nums.begin(), nums.end());
+    for (auto num : nums) {
+        std::cout << num << ' ';
+    }
+    std::cout << std::endl;
+
+    // 降冪排序 (大到小) - 使用自定義比較函式 cmpInt
+    std::sort(nums.begin(), nums.end(), cmpInt);
+    for (auto num : nums) {
+        std::cout << num << ' ';
+    }
+    std::cout << std::endl;
+
+    // ----------- struct student 排序範例 -----------
+
+    // 建立一個學生 vector
+    std::vector<student> students;
+    students.push_back(student{2, 60});
+    students.push_back(student{1, 100});
+    students.push_back(student{4, 70});
+    students.push_back(student{5, 80});
+    students.push_back(student{3, 90});
+
+    // 用 number (學號) 升冪排序
+    std::sort(students.begin(), students.end(), cmpStucdentnumberUp);
+    for (auto student : students) {
+        std::cout << '(' << student.number << ',' << student.score << ") ";
+    }
+    std::cout << std::endl;
+
+    // 用 number (學號) 降冪排序
+    std::sort(students.begin(), students.end(), cmpStucdentnumberDown);
+    for (auto student : students) {
+        std::cout << '(' << student.number << ',' << student.score << ") ";
+    }
+    std::cout << std::endl;
+
+    // 用 score (成績) 升冪排序
+    std::sort(students.begin(), students.end(), cmpStucdentScoreUp);
+    for (auto student : students) {
+        std::cout << '(' << student.number << ',' << student.score << ") ";
+    }
+    std::cout << std::endl;
+
+    // 用 score (成績) 降冪排序
+    std::sort(students.begin(), students.end(), cmpStucdentScoreDown);
+    for (auto student : students) {
+        std::cout << '(' << student.number << ',' << student.score << ") ";
+    }
+    std::cout << std::endl;
+
+    return 0;
+}
--- a/docs/vector.cpp
+++ b/docs/vector.cpp
@@ -0,0 +1,147 @@
+#include <iostream>
+#include <vector>
+
+struct student {
+    int number; // 學號
+    int score;  // 成績
+};
+
+int main(){
+    std::vector<student> students;
+    students.push_back(student{1, 100});
+    students.push_back(student{2, 90});
+    students.push_back(student{3, 80});
+    students.push_back(student{4, 70});
+    students.push_back(student{5, 60});
+
+    // ----------- 掃過 vector 中每一個值 範例 -----------
+
+    // 會改變原本的值
+    std::cout << "method 1:" << std::endl;
+    std::vector<student> s1 = students;     //從 students 複製一個一模一樣的vector
+    for (int i = 0; i < s1.size(); i++) {
+        s1[i].number = 1;
+        std::cout << '(' << s1[i].number << ',' << s1[i].score << ") ";
+    }
+    std::cout << std::endl;
+    std::cout << "original vector:" << std::endl;
+    for (auto s: s1) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    // 不會改變原本的值
+    std::cout << "method 2:" << std::endl;
+    std::vector<student> s2 = students;
+    for (auto s: s2) {              // auto也可以寫成 student
+        s.number = 2;
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl;
+    std::cout << "original vector:" << std::endl;
+    for (auto s: s2) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    // 會改變原本的值
+    std::cout << "method 3:" << std::endl;
+    std::vector<student> s3 = students;
+    for (auto& s: s3) {             // auto也可以寫成 student
+        s.number = 3;
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl;
+    std::cout << "original vector:" << std::endl;
+    for (auto& s: s3) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+    // 結論：
+    // 只要在資料型態後面加上 & (reference) 就可以改變原本的資料
+    // auto 可以自動偵測資料型態
+
+    // ----------- 取得 vector 最前面的值 範例 -----------
+    std::cout << "number: " << students.front().number << std::endl;
+    std::cout << "score: " << students.front().score << std::endl;
+
+    // ----------- 取得 vector 最後面的值 範例 -----------
+    std::cout << "number: " << students.back().number << std::endl;
+    std::cout << "score: " << students.back().score << std::endl;
+
+    // ----------- 取得 vector 最前面的指標 範例 -----------
+    std::cout << "number: " << (*students.begin()).number << std::endl;
+    std::cout << "score: " << (*students.begin()).score << std::endl;
+
+    // ----------- 取得 vector 最後面的指標 範例 -----------
+    std::cout << "number: " << (*(students.end()-1)).number << std::endl;
+    std::cout << "score: " << (*(students.end()-1)).score << std::endl;
+
+    std::cout << std::endl;
+
+    // ----------- 刪除 vector 最前面的值 範例 -----------
+    std::vector<student> s4 = students;
+    std::cout << "original vector:" << std::endl;
+    for (auto& s: s4) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl;
+
+    s4.erase(s4.begin());
+
+    std::cout << "after erase vector:" << std::endl;
+    for (auto& s: s4) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    // ----------- 刪除 vector 第i個的值 範例 -----------
+    std::vector<student> s5 = students;
+    std::cout << "original vector:" << std::endl;
+    for (auto& s: s5) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    s5.erase(s5.begin() + 1);
+
+    std::cout << "after erase vector:" << std::endl;
+    for (auto& s: s5) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    // ----------- 刪除 vector 最後面的值 範例 -----------
+    std::vector<student> s6 = students;
+    std::cout << "original vector:" << std::endl;
+    for (auto& s: s6) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    s6.erase(s6.end());
+
+    std::cout << "after erase vector:" << std::endl;
+    for (auto& s: s6) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+
+    // ----------- 清空 vector 範例 -----------
+    std::vector<student> s7 = students;
+    std::cout << "original vector:" << std::endl;
+    for (auto& s: s7) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+
+    s7.clear();
+
+    std::cout << "after clear vector:" << std::endl;
+    for (auto& s: s7) {             // auto也可以寫成 student
+        std::cout << '(' << s.number << ',' << s.score << ") ";
+    }
+    std::cout << std::endl << std::endl;
+    return 0;
+}