实验7

任务4：

 1 #include <stdio.h>
 2 
 3 #define N 80
 4 #define M 100
 5 
 6 int a = 0; 
 7 int n = 0;
 8 
 9 void read() {
10     char ch;
11     FILE *fp = fopen("C:\\Users\\HL158\\Desktop\\data4.txt", "r");
12     if (fp == NULL) {
13         perror("Unable to open file");
14         return;
15     }
16 
17     while ((ch = fgetc(fp)) != EOF) {
18         if (ch != ' ' && ch != '\n' && ch != '\t' && ch != '\r') { 
19             n++; 
20         }
21         if (ch == '\n') {
22             a++;
23         }
24     }
25 
26     if (ch != '\n') {
27         a++;
28     }
29     fclose(fp);
30 }
31 
32 int main() {
33     read(); 
34     printf("data4.txt统计结果\n");
35     printf("行数: %17d\n", a);
36     printf("字符数（不计空白符）：%d\n", n);
37     return 0;
38 }

任务5：

  1 #include <stdio.h>
  2 #include <string.h>
  3 
  4 #define N 10
  5 
  6 typedef struct {
  7     long id;            
  8     char name[20];     
  9     float objective;    
 10     float subjective;  
 11     float sum;          
 12     char result[10];    
 13 } STU;
 14 
 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...\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); 
 34     write(stu, N);  
 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 
 43 void output(STU st[], int n) {
 44     int i;
 45     
 46     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");
 47     for (i = 0; i < n; i++)
 48         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);
 49 }
 50 
 51 void read(STU st[], int n) {
 52     int i;
 53     FILE *fin;
 54 
 55     fin = fopen("examinee.txt", "r");
 56     if (!fin) {
 57         printf("fail to open file\n");
 58         return;
 59     }
 60 
 61     while (!feof(fin)) {
 62         for (i = 0; i < n; i++)
 63             fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name, &st[i].objective, &st[i].subjective);
 64     }
 65 
 66     fclose(fin);
 67 }
 68 
 69 void write(STU s[], int n) {
 70  int i;
 71     FILE *fp;
 72     fp = fopen("list_pass.txt", "w");
 73     if (fp == NULL) {
 74         printf("fail to open file to write\n");
 75         return;
 76     }
 77 
 78         for (i = 0; i < n; i++) {
 79             if(s[i].sum>=60)
 80             fprintf(fp, "%ld%10s%10.2f%10.2f%10.2f%10s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].result);
 81         }
 82   
 83 
 84     fclose(fp);
 85 }
 86 
 87 int process(STU st[], int n, STU st_pass[]) {
 88    int i,count=0;
 89    for(i=0;i<n;i++)
 90    {
 91        st[i].sum=st[i].subjective+st[i].objective;
 92        if(st[i].sum>=60){
 93            st_pass[count]=st[i];
 94        count++;
 95        strcpy(st[i].result,"通过"); 
 96    }
 97    else
 98    strcpy(st[i].result,"不通过"); 
 99    }
100    return count; 
101 }

任务6：

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #define N 100
 4 #define M 100 
 5 
 6 typedef struct {
 7     int id;      
 8     char name[N];
 9     char ban[N];     
10 } stu;
11 void read(stu s[],int n);
12 void write(stu s[],int n);
13 void process(stu s[],int n,stu ss[]);
14 void output(stu ss[],int n);
15 
16 int main(){
17     stu s[N],ss[N];
18 int i;
19 int n;
20 n=5;
21 read(s,N);
22 process(s,n,ss);
23 printf("----------随机抽点名单----------\n");
24  
25 output(ss,n);
26 printf("\n");
27 printf("----------保存到文件----------\n");
28 write(ss,n); 
29     
30     return 0;
31 }
32 void read(stu s[],int n) 
33 {
34     int i;
35       FILE *fp;
36 
37     fp = fopen("list.txt", "r");
38     if (!fp) {
39           printf("fail to open file\n");
40         return;
41     }
42 
43     while (!feof(fp)) {
44         for (i = 0; i < n; i++)
45             fscanf(fp, "%20d%10s%20s\n",&s[i].id,s[i].name,s[i].ban);
46 
47     }
48 
49     fclose(fp);
50        
51 }
52 void output(stu s[],int n){
53     int i;
54     for(i=0;i<n;i++)
55     {
56         printf("%-20d%-10s%20s\n",s[i].id,s[i].name,s[i].ban);
57      } 
58 }
59 
60 void process(stu s[], int n, stu ss[]) {
61     int i, j;
62     int used[N] = {0}; 
63     srand((unsigned)time(NULL)); 
64 
65     for (i = 0; i < n; i++) {
66         do {
67             j = rand() % 79; 
68         } while (used[j]); 
69         ss[i] = s[j]; 
70         used[j] = 1; 
71     }
72 }
73     
74 
75 void write(stu ss[],int n){
76     char x[N];
77     int i;
78     printf ("输入文件名：");
79     scanf("%s",x);
80     FILE *fp;
81     fp=fopen(x,"w");
82     if(fp==NULL){
83         
84      printf("fail");    
85     return;
86 }
87     for(i=0;i<n;i++)
88     fprintf(fp,"%-20d%-10s%-20s\n",ss[i].id,ss[i].name,ss[i].ban);
89     printf("保存成功！");
90     fclose(fp);
91     
92 }