1 #include <stdio.h>
 2 #define N 4
 3 int main() 
 4 {
 5     int a[N] = { 1, 9, 8, 4 };
 6     char b[N] = { '1', '9', '8', '4' };
 7     int i;
 8     printf("sizeof(int) = %d\n", sizeof(int));
 9     printf("sizeof(char) = %d\n", sizeof(char));
10     printf("\n");
11     // 输出一维int数组a中每个元素的地址、值
12     for (i = 0; i < N; ++i)
13         printf("%p: %d\n", &a[i], a[i]);
14     printf("\n");
15     // 输出一维char数组b中每个元素的地址、值
16     for (i = 0; i < N; ++i)
17         printf("%p: %c\n", &b[i], b[i]);
18     printf("\n");
19     // 输出数组名a和b对应的值
20     printf("a = %p\n", a);
21     printf("b = %p\n", b);
22     return 0;
23 }
24 
25 
26     
27 /*
28 ① int型数组a,在内存中是连续存放的,每个元素占用4个内存字节单元。
29 ② char型数组b,在内存中是连续存放的,每个元素占用1个内存字节单元?
30 ③ 数组名a对应的值,和&a[0]是一样的,数组名b对应的值,和&b[0]是一样的。
31 */
 1 #include <stdio.h>
 2 #define N 2
 3 #define M 4
 4 int main() {
 5     int a[N][M] = { {1, 9, 8, 4}, {2, 0, 2, 2} };
 6     char b[N][M] = { {'1', '9', '8', '4'}, {'2', '0', '2', '2'} };
 7     int i, j;
 8     // 输出二维数组a中每个元素的地址和值
 9     for (i = 0; i < N; ++i)
10         for (j = 0; j < M; ++j)
11             printf("%p: %d\n", &a[i][j], a[i][j]);
12     printf("\n");
13     // 输出二维数组a中每个元素的地址和值
14     for (i = 0; i < N; ++i)
15         for (j = 0; j < M; ++j)
16             printf("%p: %c\n", &b[i][j], b[i][j]);
17     return 0;
18 }
19 
20 
21 
22 /*
23 ① int型二维数组a,在内存中是"按行连续存放"的,每个元素占用4个内存字节单
24 元。
25 ② char型二维数组b,在内存中是"按行连续存放"的,每个元素占用1个内存字节
26 单元。
27 */
 1 #include <stdio.h>
 2 #define N 13
 3 int days_of_year(int year, int month, int day);
 4 int main() {
 5     int year, month, day;
 6     int days;
 7     while (scanf_s("%d%d%d", &year, &month, &day) != EOF) {
 8         days = days_of_year(year, month, day);
 9         printf("%4d-%02d-%02d是这一年的第%d天.\n\n", year, month, day, days);
10     }
11     return 0;
12 }
13 int days_of_year(int year, int month, int day)
14 {
15     int i, j,s;
16     j = 0;
17     if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
18         j = 1;
19     int k[N] = { 0,31,28 + j,31,30,31,30,31,31,30,31,30,31 };
20     s = 0;
21     for (i = 1; i < month; i++)
22     {
23         s += k[i];
24     }
25     s += day;
26     return s;
27 
28 }

 

 1 #include <stdio.h>
 2 #define N 5
 3 void input(int x[], int n);
 4 void output(int x[], int n);
 5 double average(int x[], int n);
 6 void bubble_sort(int x[], int n);
 7 int main() {
 8     int scores[N];
 9     double ave;
10     printf("录入%d个分数:\n", N);
11     input(scores, N);
12     printf("\n输出课程分数: \n");
13     output(scores, N);
14     printf("\n课程分数处理: 计算均分、排序...\n");
15     ave = average(scores, N);
16     bubble_sort(scores, N);
17     printf("\n输出课程均分: %.2f\n", ave);
18     printf("\n输出课程分数(高->低):\n");
19     output(scores, N);
20     return 0;
21 }
22 void input(int x[], int n) {
23     int i;
24     for (i = 0; i < n; ++i)
25         scanf_s("%d", &x[i]);
26 }
27 void output(int x[], int n) {
28     int i;
29     for (i = 0; i < n; ++i)
30         printf("%d ", x[i]);
31     printf("\n");
32 }
33 double average(int x[], int n)
34 {
35     int i;
36     double j;
37     j = 0;
38     for (i = 0; i < N; i++)
39     {
40         j += x[i];
41     }
42     j /= N;
43     return j;
44 }
45 void bubble_sort(int x[], int n)
46 {
47     int i, j, k;
48 
49     for (i = 0; i < N - 1; i++)
50     {
51         for (j = 0; j < N - i - 1; j++)
52         {
53             if (x[j] < x[j + 1])
54             {
55                 k = x[j];
56                 x[j] = x[j + 1];
57                 x[j + 1] = k;
58             }
59         }
60 
61     }
62 
63 
64 }

 

 

 1 #include <stdio.h>
 2 #include<stdlib.h>
 3 #define N 100
 4 void dec2n(int x, int n); // 函数声明
 5 int main() {
 6     int x;
 7     printf("输入一个十进制整数: ");
 8     while (scanf_s("%d", &x) != EOF) {
 9         dec2n(x, 2); // 函数调用: 把x转换成二进制输出
10         dec2n(x, 8); // 函数调用: 把x转换成八进制输出
11         dec2n(x, 16); // 函数调用: 把x转换成十六进制输出
12         printf("\n输入一个十进制整数: ");
13     }
14     return 0;
15 }
16 void dec2n(int x, int n)
17 {
18     int k[N];
19     int i, j;
20     char s[N];
21     for (i = 0; i < N; i++)
22     {
23         k[i] = x % n;
24         x /= n;
25         if (x == 0)
26             break;
27     }
28     if (n == 2 || n == 8)
29     {
30         for (j = i; j >= 0; j--)
31         {
32             printf("%d", k[j]);
33         }
34         printf("\n");
35     }
36     if (n == 16)
37     {
38         for (j = 0; j <= i; j++)
39         {
40             if (k[j] < 10)
41                 s[j] =k[j]+ 48;
42             else
43                 s[j] =k[j]+ 55;
44         }
45         for (j = i; j >= 0; j--)
46         {
47             printf("%c", s[j]);
48         }
49         printf("\n");
50     }
51     //方法2:
52     if (n == 16)
53     {
54         char standard[17] = { "0123456789ABCDEF" };
55         for (j = i; j >= 0; j--)
56         {
57             printf("%c", standard[k[j]]);
58         }
59         printf("\n");
60     }
61 }

 

 

 

 

 

 1 #include <stdio.h>
 2 #include <string.h>
 3 #define N 80
 4 int main()
 5 {
 6     char views1[N] = "hey, C, I have not love u yet.";
 7     char views2[N] = "hey, C, how can I love u?";
 8     char t[N];
 9     printf("交换前: \n");
10     printf("views1: %s\n", views1);
11     printf("views2: %s\n", views2);
12     strcpy_s(t, views1);
13     strcpy_s(views1, views2);
14     strcpy_s(views2, t);
15     printf("交换后: \n");
16     printf("views1: %s\n", views1);
17     printf("views2: %s\n", views2);
18     return 0;
19 }

 1 #include <stdio.h>
 2 #include <string.h>
 3 #define N 80
 4 int main() {
 5     char views[2][N] = { "hey, C, I have not love u yet.",
 6                            "hey, C, how can I love u?" };
 7     char t[N];
 8     printf("交换前: \n");
 9     printf("views1: %s\n", views[0]);
10     printf("views2: %s\n", views[1]);
11     // 交换
12     strcpy_s(t, views[0]);
13     strcpy_s(views[0], views[1]);
14     strcpy_s(views[1], t);
15     printf("交换后: \n");
16     printf("views1: %s\n", views[0]);
17     printf("views2: %s\n", views[1]);
18     return 0;
19 }

 

 

 

 1 #include <stdio.h>
 2 #include <string.h>
 3 
 4 #define N 5
 5 #define M 20
 6 
 7 void bubble_sort(char str[][M], int n)
 8 {
 9     char temp[M];
10     int i,j;
11     for (j = 0; j < N; j++)
12     {
13 
14         for (i = 0; i < N-j-1; i++)
15         {
16             if (strcmp(str[i], str[i + 1])>0)
17             {
18                 strcpy_s(temp, str[i]);
19                 strcpy_s(str[i], str[i + 1]);
20                 strcpy_s(str[i + 1], temp);
21             }
22         }
23     }
24    
25 
26 
27 
28 }
29 
30 int main() {
31     char name[][M] = { "Bob", "Bill", "Joseph", "Taylor", "George" };
32     int i;
33 
34     printf("输出初始名单:\n");
35     for (i = 0; i < N; i++)
36         printf("%s\n", name[i]);
37 
38     printf("\n排序中...\n");
39     bubble_sort(name, N);  // 函数调用 
40 
41     printf("\n按字典序输出名单:\n");
42     for (i = 0; i < N; i++)
43         printf("%s\n", name[i]);
44 
45     return 0;
46 }