实验7

实验4：

 1 #include <stdio.h>
 2 #include <string.h>
 3 
 4 int main() {
 5     FILE *fp;
 6     int sum = 0;
 7     char lines[100][1000]; 
 8     int i = 0, n;
 9 
10     fp = fopen("C:\\Users\\legion\\Desktop\\实验7数据文件及部分代码\\data4.txt", "r");
11     if (fp == NULL) {
12         printf("fail to open file to read\n");
13         return 0;
14     }
15 
16     while (fgets(lines[i], sizeof(lines[i]), fp)!= NULL) 
17         i++;
18     
19     n = i;
20 
21     for (int j = 0; j < n; j++) {
22         int w = strlen(lines[j]);
23         for (int m = 0; m < w; m++) {
24             if (lines[j][m] ==' '||lines[j][m]=='\t'||lines[j][m]=='\n') 
25                 w--;
26             
27         }
28         sum += w;
29     }
30     printf("data4.txt统计结果：\n");
31     printf("行数：                %d\n", n);
32     printf("字符数（不计空白符）：%d\n", sum);
33 
34     fclose(fp); 
35 
36     return 0;
37 }

实验5：

  1 #include <stdio.h>
  2 #include <string.h>
  3 
  4 #define N 10
  5 
  6 typedef struct {
  7     long id;            // 准考证号
  8     char name[20];      // 姓名
  9     float objective;    // 客观题得分
 10     float subjective;   // 操作题得分
 11     float sum;          // 总分
 12     char result[10];    // 考试结果
 13 } STU;
 14 
 15 // 函数声明
 16 void read(STU st[], int n);
 17 void write(STU st[], int n);
 18 void output(STU st[], int n);
 19 int process(STU st[], int n, STU st_pass[]);
 20 
 21 int main() {
 22     STU stu[N], stu_pass[N];
 23     int cnt;
 24     double pass_rate;
 25 
 26     printf("从文件读入%d个考生信息...\n", N);
 27     read(stu, N);
 28 
 29     printf("\n对考生成绩进行统计...\n");
 30     cnt = process(stu, N, stu_pass);
 31 
 32     printf("\n通过考试的名单:\n");
 33     output(stu, N);   // 输出所有考生完整信息到屏幕
 34     write(stu, N);    // 输出考试通过的考生信息到文件
 35 
 36     pass_rate = 1.0 * cnt / N;
 37     printf("\n本次等级考试通过率: %.2f%%\n", pass_rate*100);
 38 
 39     return 0;
 40 }
 41 
 42 // 把所有考生完整信息输出到屏幕上
 43 // 准考证号，姓名，客观题得分，操作题得分，总分，结果
 44 void output(STU st[], int n) {
 45     int i;
 46     
 47     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结果\n");
 48     for (i = 0; i < n; i++)
 49         printf("%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", st[i].id, st[i].name, st[i].objective, st[i].subjective, st[i].sum, st[i].result);
 50 }
 51 
 52 // 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
 53 void read(STU st[], int n) {
 54     int i;
 55     FILE *fin;
 56 
 57     fin = fopen("C:\\Users\\legion\\Desktop\\实验7数据文件及部分代码\\examinee.txt", "r");
 58     if (!fin) {
 59         printf("fail to open file\n");
 60         return;
 61     }
 62 
 63     while (!feof(fin)) {
 64         for (i = 0; i < n; i++)
 65             fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name, &st[i].objective, &st[i].subjective);
 66     }
 67 
 68     fclose(fin);
 69 }
 70 
 71 // 把通过考试的考生完整信息写入文件list_pass.txt
 72 // 准考证号，姓名，客观题得分，操作题得分，总分，结果
 73 void write(STU s[], int n) {
 74     int i;
 75     FILE *fp;
 76     
 77     fp = fopen("C:\\Users\\legion\\Desktop\\实验7数据文件及部分代码\\list_pass.txt","w");
 78     if(fp == NULL){
 79         printf("fail to open file to write\n");
 80         return ;
 81     }
 82     for(i=0;i<n;i++){
 83         fprintf(fp,"%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].result);
 84     }
 85     fclose(fp);
 86 }
 87 
 88 // 对考生信息进行处理：计算每位考生考试总分、结果；统计考试通过的人数
 89 int process(STU st[], int n, STU st_pass[]) {
 90    int i;
 91    int j=0;
 92    for(i=0;i<n;i++){
 93        st[i].sum=st[i].objective+st[i].subjective;
 94        if(st[i].sum>=60){
 95            strcpy(st[i].result,"通过");
 96            st_pass[j++]=st[i];
 97        }
 98     else
 99            strcpy(st[i].result,"不通过");
100    }
101    return j;
102 }

实验6：

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <time.h>
 4 
 5 #define STUDENT_NUM 80
 6 
 7 typedef struct {
 8     int id;
 9     char name[20];
10     char class[20];
11 } Student;
12 
13 void swap(Student *a, Student *b) {
14     Student temp = *a;
15     *a = *b;
16     *b = temp;
17 }
18 
19 void random(Student students[], int n, Student selected[], int m) {
20     srand((unsigned int)time(NULL));
21     int i, j;
22     for (i = 0; i < n; i++) {
23         j = rand() % (n - i) + i;
24         swap(&students[i], &students[j]);
25     }
26     for (i = 0; i < m; i++) 
27         selected[i] = students[i];
28     
29 }
30 
31 void output(Student students[], int n) {
32     int i;
33     for (i = 0; i < n; i++) 
34         printf("%d  %s  %s\n", students[i].id, students[i].name, students[i].class);
35 }
36 
37 
38 void write(Student students[], int n, char *filename) {
39     FILE *fp;
40     int i;
41     fp = fopen(filename, "w");
42     if (fp == NULL) {
43         printf("无法打开文件\n");
44         return;
45     }
46     for (i = 0; i < n; i++) 
47         fprintf(fp, "%d %s %s\n", students[i].id, students[i].name, students[i].class);
48     printf("保存成功！\n");
49     fclose(fp);
50 }
51 
52 int main() {
53     Student students[STUDENT_NUM];
54     Student selected[5];
55     char filename[100];
56     int i;
57     
58     for (i = 0; i < STUDENT_NUM; i++) {
59         students[i].id = 204942000 + i;
60         sprintf(students[i].name,  "学生%d", i + 1);
61         sprintf(students[i].class,  "星际联盟2049(1)班");
62     }
63     random(students, STUDENT_NUM, selected, 5);
64     printf("---------随机抽取名单-----------：\n");
65     output(selected, 5);
66     printf("---------保存到文件-----------：\n");
67     printf("请输入文件名：");
68     scanf("%s", filename);
69     write(selected, 5, filename);
70     return 0;
71 }