实验2 C语言分支与循环基础应用编程

task1.c

问题一：生成1~65中的随机数

问题二：随机生成5个本班学号

task2.c

 1 #include <stdio.h>
 2 int main()
 3 {
 4     char colour;
 5     printf("请输入交通信号灯的颜色：");
 6     while ((colour = getchar()) != EOF)
 7     {
 8         switch (colour) 
 9         {
10         case 'r':
11             printf("stop!\n");
12             break;
13         case 'g':
14             printf("go go go\n");
15             break;
16         case 'y':
17             printf("wait a minute\n");
18             break;
19         default:
20             printf("something must be wrong\n");
21         }
22         getchar();
23     }
24     return 0;
25 }

task3.c

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <time.h>
 4 int main()
 5 {
 6     printf("猜猜2024年5月哪一天会是你的lucky day\n");
 7     int luckyday,guess,i;
 8     srand(time(0));
 9     luckyday = rand() % 31 + 1;
10     printf("开始喽，你有三次机会，猜吧：");
11     for (i = 0; i < 3; i++)
12     {
13         scanf("%d", &guess);
14         if (guess == luckyday)
15         {
16             printf("猜中了\n");
17             return 0;
18         }
19         else if (guess > luckyday)
20                 printf("猜晚了\n");
21         else
22                 printf("猜早了\n");
23     }
24     if (i = 3)
25         printf("次数用完啦，悄悄告诉你，5月你的lucky day是%d号", luckyday);
26 
27     return 0;
28 }

 task4.c

 1 #include <stdio.h>
 2 int main()
 3 {
 4     double s = 0,down=0;
 5     int i,n,a;
 6     while (scanf("%d%d", &n, &a) != EOF)
 7     {
 8         for (i = 1; i <= n; i++)
 9         {
10             down = 10 * down + (double)a;
11             s += i / down;
12         }
13         printf("s=%lf\n", s);
14         s = 0;
15         down = 0;
16     }
17     return  0;
18 }

task5.c

 1 #include <stdio.h>
 2 int main()
 3 {
 4     int column, line, value;
 5     for (column = 1; column <= 9; column++)
 6     {
 7         for (line = 1; line <= column; line++)
 8         {
 9             value = column * line;
10             printf("%dx%d =%4d  ", line, column, value);
11             if (line == column)
12                 printf("\n");
13         }
14     }
15     return 0;
16 }

task6.c

 1 #include <stdio.h>
 2 int main()
 3 {
 4     int n,i,j;
 5     scanf("%d", &n);
 6     for (i=n;i>0;i--)
 7     {
 8         for (j = 0; j < n - i; j++)
 9         {
10             printf("   \t");
11         }
12         for (j = 0; j < (2 * i - 1); j++)
13         {
14             printf(" O \t");
15         }
16         printf("\n");
17         for (j = 0; j < n - i; j++)
18         {
19             printf("   \t");
20         }
21         for (j = 0; j < (2 * i - 1); j++)
22         {
23             printf("<H>\t");
24         }
25         printf("\n");
26         for (j = 0; j < n - i; j++)
27         {
28             printf("   \t");
29         }
30         for (j = 0; j < (2 * i - 1); j++)
31         {
32             printf("I I\t");
33         }
34         printf("\n");
35         
36     }
37     return 0;
38 }
39