实验7

4.task4

 1 #include <stdio.h>
 2 
 3 int main() {
 4     char ch;
 5     int k=0;
 6     FILE *fp;
 7 
 8     fp = fopen("data4.txt", "r");
 9     if(fp == NULL) {
10         printf("fail to open file\n");
11         return 1;
12     }
13     while((ch=fgetc(fp))!=EOF)
14     {
15         if(ch!=' '&&ch!='\n'&&ch!='\t'&&ch!='\v')
16             k++;
17     }
18     
19 
20     fclose(fp);
21     printf("data4.txt中共包含字符数（不计空白符）:%d\n",k);
22     return 0;
23 }

5.task5

  1 #include <stdio.h>
  2 #include <string.h>
  3 #include <stdlib.h>
  4 
  5 #define N 10
  6 
  7 typedef struct {
  8     long int id;
  9     char name[20];
 10     float objective;    // 客观题得分
 11     float subjective;   // 操作题得分
 12     float sum;
 13     char level[10];
 14 } STU;
 15 
 16 // 函数声明
 17 void input(STU s[], int n);
 18 void output(STU s[], int n);
 19 void process(STU s[], int n);
 20 
 21 int main() {
 22     STU stu[N];
 23 
 24     printf("从文件读入%d个考生信息: 准考证号，姓名，客观题得分(<=40)，操作题得分(<=60)\n", N);
 25     input(stu, N);
 26 
 27     printf("\n对考生信息进行处理: 计算总分，确定等级\n");
 28     process(stu, N);
 29 
 30     printf("\n打印考生完整信息, 并保存到文件中");
 31     output(stu, N);
 32 
 33     return 0;
 34 }
 35 
 36 // 从文本文件examinee.txt读入考生信息:准考证号，姓名，客观题得分，操作题得分
 37 void input(STU s[], int n) {
 38     int i;
 39     FILE *fin;
 40 
 41     fin = fopen("examinee.txt", "r");
 42     if (fin == NULL) {
 43         printf("fail to open file\n");
 44         exit(0);
 45     }
 46 
 47     while (!feof(fin)) {
 48         for (i = 0; i < n; i++)
 49             fscanf(fin, "%ld %s %f %f", &s[i].id, s[i].name, &s[i].objective, &s[i].subjective);
 50     }
 51 
 52     fclose(fin);
 53 }
 54 
 55 // 输出考生完整信息: 准考证号，姓名，客观题得分，操作题得分，总分，等级
 56 // 不仅输出到屏幕上，还写到文本文件result.txt中
 57 void output(STU s[], int n) {
 58     FILE *fout;
 59     int i;
 60     
 61     // 输出到屏幕
 62     printf("\n");
 63     printf("准考证号\t姓名\t客观题得分\t操作题得分\t总分\t\t等级\n");
 64     for (i = 0; i < n; i++)
 65         printf("%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].level);
 66     
 67     // 保存到文件 
 68     fout = fopen("result.txt", "w");
 69     if (!fout) {
 70         printf("fail to open or create result.txt\n");
 71         exit(0);
 72     }
 73     
 74     fprintf(fout, "准考证号\t\t姓名\t客观题得分\t操作题得分\t总分\t\t等级\n");
 75 
 76     for (i = 0; i < n; i++)
 77         fprintf(fout, "%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].level);
 78 
 79     fclose(fout);
 80 }
 81 
 82 // 对考生信息进行处理：计算总分，排序，确定等级
 83 void process(STU s[], int n) {
 84     int i;
 85     int j;
 86     STU h;
 87     for(i=0;i<N;i++)
 88     {
 89         s[i].sum=s[i].objective+s[i].subjective;
 90     }
 91     for(i=0;i<N-1;i++)
 92     {
 93         for(j=0;j<N-1-i;j++)
 94         {
 95             if(s[j].sum<s[j+1].sum)
 96             {
 97                 h=s[j];
 98                 s[j]=s[j+1];
 99                 s[j+1]=h;
100             }
101         }
102     }
103     for(i=0;i<N*0.1;i++)
104         strcpy(s[i].level,"优秀");
105     for(i=N*0.1;i<N*0.5;i++)
106         strcpy(s[i].level,"合格");
107     for(i=N*0.5;i<N;i++)
108         strcpy(s[i].level,"不合格");
109 
110 }

6.task6

 1 #include <stdio.h>
 2 #include<stdlib.h>
 3 #include<time.h>
 4 #define N 5
 5 #define M 20
 6 typedef struct
 7 {
 8     long int  id;
 9     char name[20];
10     char clas[20];
11 }STU;
12 
13 int main() {
14     int i;
15     int n;
16     STU s[M],r[N];
17 
18     FILE *fp,*fout;
19 
20     fp=fopen("list.txt", "r");
21     fout=fopen("lucky.txt","w");
22 
23     if(fp == NULL) 
24     {
25         printf("fail to open file\n");
26         return 1;
27     }
28 
29     while(!feof(fp))
30     {
31         for(i=0;i<M;i++)
32         {
33         fscanf(fp,"%ld%s%s",&s[i].id,s[i].name,s[i].clas);
34         }
35     }
36 
37     srand(time(NULL));
38 
39     for(i=0;i<N;i++)
40     {
41         n=rand()%M;
42         r[i]=s[n];
43     }
44 
45     fclose(fp);
46 
47     if(fout==NULL)
48     {
49         printf("fail to open file\n");
50         return 1;
51     }
52 
53     for (i=0;i<N;i++)
54     {
55         fprintf(fout,"%ld\t\t%s\t\t%s\n", r[i].id, r[i].name,r[i].clas);
56         printf("%ld\t\t%s\t\t%s\n", r[i].id, r[i].name, r[i].clas);
57     }
58     fclose(fout);
59     return 0;
60 }