实验七

task4.c

源代码：

 1 #define _CRT_SECURE_NO_WARNINGS 1
 2 #include <stdio.h>
 3 #include <stdlib.h>
 4 int main() {
 5     FILE *fp = fopen("C:\\Users\\李超然\\Documents\\Visual Studio 2010\\Projects\\实验4\\实验4\\Debug\\data4.txt", "r");
 6     if (!fp) {
 7         printf("打开文件失败\n");
 8         system("pause");
 9         return 1;
10     }
11     int ch;
12     int line = 0;    
13     int charCnt = 0; 
14     int isNewLine = 1; 
15 
16     while ((ch = fgetc(fp)) != EOF) {
17         if (ch == ' ' || ch == '\t' || ch == '\n') {
18             if (ch == '\n') {
19                 line++;
20                 isNewLine = 1;
21             }
22             continue;
23         }
24         charCnt++;
25         isNewLine = 0;
26     }
27     if (!isNewLine) line++;
28 
29     fclose(fp);
30     printf("data4.txt统计结果:\n");
31     printf("行数: %d\n", line);
32     printf("字符数(不计空白符): %d\n", charCnt);
33     system("pause");
34     return 0;
35 }
View Code

运行结果截图：

4

 

task5.c

源代码：

 1 #define _CRT_SECURE_NO_WARNINGS 1
 2 #include <stdio.h>
 3 #include <string.h>
 4 #include <stdlib.h>
 5 #define N 10
 6 
 7 typedef struct {
 8     long id;
 9     char name[20];
10     float objective;
11     float subjective;
12     float sum;
13     char result[10];
14 } STU;
15 
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: 已完成\n", N);
27     read(stu, N);
28 
29     printf("\n对考生成绩进行统计: 已完成\n");
30     cnt = process(stu, N, stu_pass);
31 
32     printf("\n所有考生完整信息:\n");
33     output(stu, N);
34 
35     printf("\n通过考试的名单写入文件: 已完成!\n");
36     write(stu_pass, cnt);
37 
38     pass_rate = 1.0 * cnt / N;
39     printf("\n本次等级考试通过率: %.2f%%\n", pass_rate * 100);
40 
41     system("pause");
42     return 0;
43 }
44 
45 void output(STU st[], int n) {
46     int i;
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",
50                st[i].id, st[i].name, st[i].objective,
51                st[i].subjective, st[i].sum, st[i].result);
52 }
53 
54 void read(STU st[], int n) {
55     int i;
56     FILE *fin;
57     // 绝对路径，精准锁定当前文件夹里的文件
58     fin = fopen("C:\\Users\\李超然\\Documents\\Visual Studio 2010\\Projects\\实验7\\实验7\\Debug\\examinee.txt", "r");
59     if (!fin) {
60         printf("fail to open examinee.txt文件\n");
61         system("pause");
62         exit(1);
63     }
64     for (i = 0; i < n; i++)
65         fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name,
66                &st[i].objective, &st[i].subjective);
67     fclose(fin);
68 }
69 
70 int process(STU st[], int n, STU st_pass[]) {
71     int passNum = 0;
72     for (int i = 0; i < n; i++) {
73         st[i].sum = st[i].objective + st[i].subjective;
74         if (st[i].sum >= 60) {
75             strcpy(st[i].result, "通过");
76             st_pass[passNum++] = st[i];
77         } else {
78             strcpy(st[i].result, "未通过");
79         }
80     }
81     return passNum;
82 }
83 
84 void write(STU st[], int n) {
85     FILE *fp = fopen("C:\\Users\\李超然\\Documents\\Visual Studio 2010\\Projects\\实验7\\实验7\\Debug\\list_pass.txt", "w");
86     if (!fp) {
87         printf("写入文件失败！\n");
88         return;
89     }
90     fprintf(fp, "准考证号\t姓名\t客观题得分\t操作题得分\t总分\t结果\n");
91     for (int i = 0; i < n; i++) {
92         fprintf(fp, "%ld\t%s\t%.2f\t%.2f\t%.2f\t%s\n",
93                 st[i].id, st[i].name, st[i].objective,
94                 st[i].subjective, st[i].sum, st[i].result);
95     }
96     fclose(fp);
97 }
View Code

运行结果截图：

7

6.1

 

task6.c

源代码：

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <time.h>
 4 #include <string.h>
 5 #define STU_MAX 80
 6 
 7 typedef struct {
 8     char id[20];
 9     char name[20];
10     char cls[30];
11 } Student;
12 
13 void sortStu(Student arr[], int n) {
14     for (int i = 0; i < n - 1; i++) {
15         for (int j = 0; j < n - i - 1; j++) {
16             if (strcmp(arr[j].id, arr[j+1].id) > 0) {
17                 Student t = arr[j];
18                 arr[j] = arr[j+1];
19                 arr[j+1] = t;
20             }
21         }
22     }
23 }
24 
25 int main() {
26     FILE *fp = fopen("C:\\Users\\李超然\\Documents\\Visual Studio 2010\\Projects\\实验7\\实验7\\Debug\\list.txt", "r");
27     if (!fp) {
28         printf("无法打开list.txt\n");
29         system("pause");
30         return 1;
31     }
32     Student allStu[STU_MAX];
33     int total = 0;
34     while (fscanf(fp, "%s %s %s", allStu[total].id, allStu[total].name, allStu[total].cls) == 3) {
35         total++;
36     }
37     fclose(fp);
38 
39     int flag[STU_MAX] = {0};
40     Student win[5];
41     int winCnt = 0;
42     srand((unsigned)time(NULL));
43 
44     while (winCnt < 5) {
45         int idx = rand() % total;
46         if (flag[idx] == 0) {
47             flag[idx] = 1;
48             win[winCnt++] = allStu[idx];
49         }
50     }
51 
52     sortStu(win, 5);
53 
54     printf("=====中奖名单=====\n");
55     for (int i = 0; i < 5; i++) {
56         printf("%s %s %s\n", win[i].id, win[i].name, win[i].cls);
57     }
58 
59     time_t now = time(NULL);
60     struct tm *t = localtime(&now);
61     char fileName[50];
62     strftime(fileName, sizeof(fileName), "%Y%m%d.txt", t);
63 
64     FILE *fw = fopen(fileName, "w");
65     for (int i = 0; i < 5; i++) {
66         fprintf(fw, "%s %s %s\n", win[i].id, win[i].name, win[i].cls);
67     }
68     fclose(fw);
69     printf("文件%s保存成功！\n", fileName);
70 
71     system("pause");
72     return 0;
73 }
View Code

运行测试截图：

666

 

实验总结：

1.在实际操作中理清了 VS2010 下相对路径与绝对路径的使用差异：程序运行时默认在项目的Debug文件夹下查找文本文件，之前多次出现 “无法打开 xxx.txt” 报错，都是文件存放位置错误导致，学会了通过绝对路径锁定文件位置来规避路径查找问题。

2.理解fopen、fscanf、fprintf、fclose等文件操作函数的使用规则，明确文件打开模式r只读、w覆盖写入的区别。

 

posted @ 2026-06-23 18:52  everleaf1616  阅读(8)  评论(0)    收藏  举报