1 #include <stdio.h>
 2 #define N 10
 3 typedef struct {
 4 char isbn[20]; // isbn號
 5 char name[80]; // 書名
 6 char author[80]; // 作者
 7 double sales_price; // 售價
 8 int sales_count; // 銷售冊數
 9 } Book;
10 
11 void output(Book x[], int n);
12 void sort(Book x[], int n);
13 double sales_amount(Book x[], int n);
14 
15 int main() {
16 Book x[N] = {
17 {"978-7-5327-6082-4", "門將之死", "羅納德.倫", 42, 51},
18 {"978-7-308-17047-5", "自由與愛之地：入以色列記", "雲也退", 49 , 30},
19 {"978-7-5404-9344-8", "倫敦人", "克萊格泰勒", 68, 27},
20 {"978-7-5447-5246-6", "軟件體的生命週期", "特德姜", 35, 90},
21 {"978-7-5722-5475-8", "芯片簡史", "汪波", 74.9, 49},
22 {"978-7-5133-5750-0", "主機戰爭", "布萊克.J.哈里斯", 128, 42},
23 {"978-7-2011-4617-1", "世界盡頭的咖啡館", "約翰·史崔勒基", 22.5, 44},
24 {"978-7-5133-5109-6", "你好外星人", "英國未來出版集團", 118, 42},
25 {"978-7-1155-0509-5", "無窮的開始:世界進步的本源", "戴維·多伊奇", 37.5,55},
26 {"978-7-229-14156-1", "源泉", "安.蘭德", 84, 59}
27 };
28 printf("圖書銷量排名(按銷售冊數): \n");
29 sort(x, N);
30 output(x, N);
31 printf("\n圖書銷售總額: %.2f\n", sales_amount(x, N));
32 return 0;
33 }
34 void output(Book x[], int n) {
35     printf("ISBN號               書名                          作者            售價    銷售冊數\n");
36     printf("------------------------------------------------------------------------------------\n");
37     
38     for (int i = 0; i < n; i++) {
39         printf("%-20s %-30s %-15s %-8.2f %-8d\n", 
40                x[i].isbn, 
41                x[i].name, 
42                x[i].author, 
43                x[i].sales_price, 
44                x[i].sales_count);
45     }
46 }
47 void sort(Book x[], int n) {
48     for (int i = 0; i < n - 1; i++) {
49         for (int j = 0; j < n - i - 1; j++) {
50             if (x[j].sales_count < x[j + 1].sales_count) {
51                 Book temp = x[j];
52                 x[j] = x[j + 1];
53                 x[j + 1] = temp;
54             }
55         }
56     }
57 }
58 double sales_amount(Book x[], int n) {
59     double total = 0.0;
60     for (int i = 0; i < n; i++) {
61         total += x[i].sales_price * x[i].sales_count;
62     }
63     return total;
64 }

1 #include <stdio.h>
 2 typedef struct {
 3 int year;
 4 int month;
 5 int day;
 6 } Date;
 7 // 函數聲明
 8 void input(Date *pd); // 輸入日期給pd指向的Date變量
 9 int day_of_year(Date d); // 返回日期d是這一年的第多少天
10 int compare_dates(Date d1, Date d2); // 比較兩個日期:
11 // 如果d1在d2之前，返回-1;
12 // 如果d1在d2之後，返回1
13 // 如果d1和d2相同，返回0
14 void test1() {
15 Date d;
16 int i;
17 printf("輸入日期:(以形如2025-12-19這樣的形式輸入)\n");
18 for(i = 0; i < 3; ++i) {
19 input(&d);
20 printf("%d-%02d-%02d是這一年中第%d天\n\n", d.year, d.month, d.day,
21 day_of_year(d));
22 }
23 }
24 void test2() {
25 Date Alice_birth, Bob_birth;
26 int i;
27 int ans;
28 printf("輸入Alice和Bob出生日期:(以形如2025-12-19這樣的形式輸入)\n");
29 for(i = 0; i < 3; ++i) {
30 input(&Alice_birth);
31 input(&Bob_birth);
32 ans = compare_dates(Alice_birth, Bob_birth);
33 if(ans == 0)
34 printf("Alice和Bob一樣大\n\n");
35 else if(ans == -1)
36 printf("Alice比Bob大\n\n");
37 else
38 printf("Alice比Bob小\n\n");
39 }
40 }
41 int main() {
42 printf("測試1: 輸入日期, 打印輸出這是一年中第多少天\n");
43 test1();
44 printf("\n測試2: 兩個人年齡大小關係\n");
45 test2();
46 }
47 int is_leap_year(int year) {
48     return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
49 }
50 void input(Date *pd){
51     scanf("%d-%d-%d",&pd->year,&pd->month,&pd->day);
52 }
53 int day_of_year(Date d) {
54     int days_in_month[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
55     int total_days = 0;
56     
57     if (is_leap_year(d.year)) {
58         days_in_month[1] = 29;
59     }
60     
61     for (int i = 0; i < d.month - 1; i++) {
62         total_days += days_in_month[i];
63     }
64     total_days += d.day;
65     return total_days;
66 }
67 int compare_dates(Date d1, Date d2) {
68     if (d1.year < d2.year) return -1;
69     if (d1.year > d2.year) return 1;
70     
71     if (d1.month < d2.month) return -1;
72     if (d1.month > d2.month) return 1;
73     
74     if (d1.day < d2.day) return -1;
75     if (d1.day > d2.day) return 1;
76     
77     return 0;
78 }

1 #include <stdio.h>
 2 #include <string.h>
 3 enum Role {admin, student, teacher};
 4 typedef struct {
 5 char username[20]; // 用户名
 6 char password[20]; // 密碼
 7 enum Role type; // 賬户類型
 8 } Account;
 9 // 函數聲明
10 void output(Account x[], int n); // 輸出賬户數組x中n個賬户信息，其中，密碼用*替代顯示
11 int main() {
12 Account x[] = {{"A1001", "123456", student},
13 {"A1002", "123abcdef", student},
14 {"A1009", "xyz12121", student},
15 {"X1009", "9213071x", admin},
16 {"C11553", "129dfg32k", teacher},
17 {"X3005", "921kfmg917", student}};
18 int n;
19 n = sizeof(x)/sizeof(Account);
20 output(x, n);
21 return 0;
22 }
23 void output(Account x[], int n) {
24     for (int i = 0; i < n; i++) {
25         int len = strlen(x[i].password);
26 
27         printf("用户名: %s\n", x[i].username);
28         
29         printf("密碼: ");
30         for (int j = 0; j < len; j++) {
31             printf("*");
32         }
33         printf("\n");
34         
35         printf("賬户類型: ");
36         switch (x[i].type) {
37             case admin:
38                 printf("admin\n");
39                 break;
40             case student:
41                 printf("student\n");
42                 break;
43             case teacher:
44                 printf("teacher\n");
45                 break;
46         }
47         
48         printf("------------------------\n");
49     }
50 }

1 #include <stdio.h>
 2 #include <string.h>
 3 typedef struct {
 4 char name[20]; // 姓名
 5 char phone[12]; // 手機號
 6 int vip; // 是否為緊急聯繫人，是取1；否則取0
 7 } Contact;
 8 // 函數聲明
 9 void set_vip_contact(Contact x[], int n, char name[]); // 設置緊急聯繫人
10 void output(Contact x[], int n); // 輸出x中聯繫人信息
11 void display(Contact x[], int n); // 按聯繫人姓名字典序升序顯示信息，緊急聯繫人最先顯示
12 #define N 10
13 int main() {
14 Contact list[N] = {{"劉一", "15510846604", 0},
15 {"陳二", "18038747351", 0},
16 {"張三", "18853253914", 0},
17 {"李四", "13230584477", 0},
18 {"王五", "15547571923", 0},
19 {"趙六", "18856659351", 0},
20 {"周七", "17705843215", 0},
21 {"孫八", "15552933732", 0},
22 {"吳九", "18077702405", 0},
23 {"鄭十", "18820725036", 0}};
24 int vip_cnt, i;
25 char name[20];
26 printf("顯示原始通訊錄信息: \n");
27 output(list, N);
28 printf("\n輸入要設置的緊急聯繫人個數: ");
29 scanf("%d", &vip_cnt);
30 printf("輸入%d個緊急聯繫人姓名:\n", vip_cnt);
31 for(i = 0; i < vip_cnt; ++i) {
32 scanf("%s", name);
33 set_vip_contact(list, N, name);
34 }
35 printf("\n顯示通訊錄列表:(按姓名字典序升序排列,緊急聯繫人最先顯示)\n");
36 display(list, N);
37 return 0;
38 }
39 void set_vip_contact(Contact x[], int n, char name[]) {
40     for (int i = 0; i < n; i++) {
41         if (strcmp(x[i].name, name) == 0) { 
42             x[i].vip = 1; 
43             break;
44         }
45     }
46 }
47 void display(Contact x[], int n) {
48     int i, j;
49     Contact temp;
50     
51     for (i = 0; i < n - 1; i++) {
52         for (j = 0; j < n - 1 - i; j++) {
53             int need_swap = 0;
54             
55             if (x[j].vip < x[j + 1].vip) {
56                 need_swap = 1;
57             } 
58             else if (x[j].vip == x[j + 1].vip && strcmp(x[j].name, x[j + 1].name) > 0) {
59                 need_swap = 1;
60             }
61             
62             if (need_swap) {
63                 temp = x[j];
64                 x[j] = x[j + 1];
65                 x[j + 1] = temp;
66             }
67         }
68     }
69     
70     for (i = 0; i < n; i++) {
71         printf("%-10s %-15s", x[i].name, x[i].phone); 
72         if (x[i].vip) {
73             printf(" *"); 
74         }
75         printf("\n");
76     }
77 }
78 void output(Contact x[], int n) {
79     int i;
80     for (i = 0; i < n; ++i) {
81         printf("%s %s", x[i].name, x[i].phone);
82         if (x[i].vip)
83             printf(" *");
84         printf("\n");
85     }
86 }