实验任务四：
源代码：
task4.c
1 #define _CRT_SECURE_NO_WARNINGS
2 #include <stdio.h>
3 #define N 10000
4
5 int main() {
6 char ch[N];
7 int line = 1;
8 int n = 0;
9 int j = 0;
10 FILE* fp;
11 fp = fopen("C:/Users/lenovo/Desktop/实验7数据文件及部分代码/data4.txt", "r");
12 if (fp == NULL) {
13 printf("Failed to open the file for reading.\n");
14 return 0;
15 }
16 int i = 0;
17 int readChar;
18 while ((readChar = fgetc(fp)) != EOF) {
19 ch[i] = readChar;
20 if (ch[i] == '\n') {
21 line++;
22 }
23 if (ch[i] == '\n' || ch[i] == ' ' || ch[i] == '\t') {
24 j++;
25 }
26 i++;
27 }
28 n = i - j;
29 fclose(fp);
30 printf("data4.txt 统计结果:\n");
31 printf("%-20s: %-20d\n", "行数", line);
32 printf("%-20s: %-20d\n", "字符数（不计空白格）", n);
33 return 0;
34 }
运行结果：
实验任务五：
源代码：
task5.c
1 #define _CRT_SECURE_NO_WARNINGS
2 #include<stdio.h>
3 #include<string.h>
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 void read(STU st[], int n);
16 void write(STU st[], int n);
17 void output(STU st[], int n);
18 int process(STU st[], int n, STU st_pass[]);
19
20 int main() {
21 STU stu[N], stu_pass[N];
22 int cnt;
23 double pass_rate;
24
25 printf("从文件读入%d个考生信息……\n", N);
26 read(stu, N);
27
28 printf("\n对考生成绩进行统计...");
29 cnt = process(stu, N, stu_pass);
30
31 printf("\n通过考试的名单：\n");
32 output(stu, N);
33 write(stu, N);
34
35 pass_rate = 1.0 * cnt / N;
36 printf("\n本次等级考试通过率： %.2f%%\n", pass_rate * 100);
37
38 return 0;
39 }
40
41 void output(STU st[], int n) {
42 int i;
43 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");
44 for (i = 0; i < n; i++)
45 printf("%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", st[i].id,
46 st[i].name, st[i].objective, st[i].subjective, st[i].sum, st[i].result);
47 }
48 void read(STU st[], int n) {
49 int i;
50 FILE* fin;
51 fin = fopen("C:\\Users\\lenovo\\Desktop\\实验7数据文件及部分代码\\examinee.txt", "r");
52 if (!fin) {
53 printf("fail to open file\n");
54 return;
55 }
56 while (!feof(fin)) {
57 for (i = 0; i < n; i++)
58 fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name,
59 &st[i].objective, &st[i].subjective);
60 }
61 fclose(fin);
62 }
63
64 void write(STU st[], int n) {
65 int i;
66 FILE* fp;
67
68 fp = fopen("list_pass.txt", "w");
69
70 if (fp == NULL) {
71 printf("fail to open file to write\n");
72 return;
73 }
74
75 fprintf(fp, "%-20s%-20s%-20s%-20s%-20s%-20s\n", "准考证号", "姓名", "客观题得分", "操作题得分", "总分", "结果");
76 for (i = 0; i < n; i++) {
77 if (st[i].sum >= 60)
78 fprintf(fp, "%-20ld%-20s%-20.2f%-20.2f%-20.2f%-20s\n", st[i].id,
79 st[i].name, st[i].objective, st[i].subjective, st[i].sum, st[i].result);
80 }
81 fclose(fp);
82 }
83
84 int process(STU st[], int n, STU st_pass[]) {
85 int i, cnt = 0;
86
87 for (i = 0; i < n; i++) {
88 st[i].sum = st[i].objective + st[i].subjective;
89
90 if (st[i].sum >= 60) {
91 strcpy(st[i].result, "通过");
92 st_pass[cnt++] = st[i];
93 }
94 else
95 strcpy(st[i].result, "不通过");
96 }
97 return cnt;
98 }
运行结果：
实验任务六：
源代码：
task6.c
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <time.h>
4
5 #define N 80
6 #define M 64
7 #define K 5
8
9 int main() {
10 char** s = (char**)malloc(N * sizeof(char*));
11 if (!s) {
12 perror("内存分配失败");
13 return 1;
14 }
15
16 for (int i = 0; i < N; i++) {
17 s[i] = (char*)malloc(M * sizeof(char));
18 if (!s[i]) {
19 for (int j = 0; j < i; j++) {
20 free(s[j]);
21 }
22 free(s);
23 perror("内存分配失败");
24 return 1;
25 }
26 }
27
28 FILE* f = fopen("C:/Users/lenovo/Desktop/实验7数据文件及部分代码/list.txt", "r");
29 if (!f) {
30 perror("无法打开输入文件");
31 for (int i = 0; i < N; i++) {
32 free(s[i]);
33 }
34 free(s);
35 return 1;
36 }
37
38 int j = 0;
39 while (fgets(s[j], M, f) != NULL) {
40 j++;
41 }
42 fclose(f);
43
44 int m[N];
45 for (int i = 0; i < N; i++) {
46 m[i] = 0;
47 }
48
49 int p[K];
50 int c = 0;
51 srand((unsigned)time(NULL));
52 while (c < K) {
53 int r = rand() % N;
54 if (m[r] == -1) {
55 continue;
56 }
57 else {
58 m[r] = -1;
59 p[c++] = r;
60 }
61 }
62
63 for (int i = 0; i < K - 1; i++) {
64 for (int j = i + 1; j < K; j++) {
65 if (strcmp(s[p[i]], s[p[j]]) > 0) {
66 int t = p[i];
67 p[i] = p[j];
68 p[j] = t;
69 }
70 }
71 }
72
73 printf("-----------随机抽点名单-----------\n");
74 for (int i = 0; i < K; i++) {
75 printf("%s", s[p[i]]);
76 }
77
78 char fn[16];
79 printf("\n-----------保存到文件-----------\n输入文件名：");
80 scanf_s("%s", fn);
81 FILE* fo = fopen(fn, "w");
82 if (!fo) {
83 perror("无法打开输出文件");
84 return 1;
85 }
86
87 for (int i = 0; i < K; i++) {
88 fprintf(fo, "%s", s[p[i]]);
89 }
90 fclose(fo);
91 printf("\n文档保存成功！");
92
93 for (int i = 0; i < N; i++) {
94 free(s[i]);
95 }
96 free(s);
97
98 return 0;
99 }
运行结果：
选做：
1 #define _CRT_SECURE_NO_WARNINGS
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <time.h>
5
6 #define N 80
7
8 typedef struct {
9 char num[20];
10 char name[20];
11 char class[40];
12 } STU;
13
14 STU st[N];
15 STU stu[5];
16
17 void read();
18 void func();
19 void bubble();
20
21 int main() {
22 read();
23 func();
24 return 0;
25 }
26
27 void read() {
28 FILE* fin = fopen("C:\\Users\\lenovo\\Desktop\\实验7数据文件及部分代码\\list.txt", "r");
29 if (!fin) {
30 printf("无法打开文件进行读取\n");
31 return;
32 }
33 int number;
34 int i = 0;
35 while (1) {
36 number = fscanf(fin, "%s %s %s", st[i].num, st[i].name, st[i].class);
37 if (number != 3) {
38 break;
39 }
40 i++;
41 }
42 fclose(fin);
43 }
44
45 void func() {
46 srand(time(NULL));
47 int cnt[5] = { 0 };
48 int sign;
49 for (int i = 0; i < 5; ) {
50 int t = rand() % 80;
51 sign = 1;
52 for (int j = 0; j < 5; j++) {
53 if (cnt[j] == t) {
54 sign = 0;
55 break;
56 }
57 }
58 if (sign) {
59 cnt[i] = t;
60 i++;
61 }
62 }
63
64 time_t ct;
65 time(&ct);
66 struct tm* p;
67 p = localtime(&ct);
68 char currenttime[20];
69 strftime(currenttime, sizeof(currenttime), "%Y%m%d", p);
70 printf("当前时间：%s\n", currenttime);
71 printf("-------------%s抽点名单--------------------\n", currenttime);
72 char fn[20];
73 sprintf(fn, "%s.txt", currenttime);
74 FILE* fp = fopen(fn, "w");
75 if (!fp) {
76 printf("无法打开文件进行写入\n");
77 return;
78 }
79 for (int i = 0; i < 5; i++) {
80 stu[i] = st[cnt[i]];
81 }
82 bubble();
83 for (int i = 0; i < 5; i++) {
84 printf("%-20s %-20s %-40s\n", stu[i].num, stu[i].name, stu[i].class);
85 fprintf(fp, "%-20s %-20s %-40s\n", stu[i].num, stu[i].name, stu[i].class);
86 }
87 printf("\n文件保存成功！\n");
88 fclose(fp);
89 }
90
91 void bubble() {
92 for (int i = 0; i < 4; i++) {
93 for (int j = 0; j < 4 - i; j++) {
94 if (strcmp(stu[j].num, stu[j + 1].num) > 0) {
95 STU temp = stu[j];
96 stu[j] = stu[j + 1];
97 stu[j + 1] = temp;
98 }
99 }
100 }
101 }
运行结果：
标签：文件,stu,int,编程,st,++,STU,实验,printf From： https://www.cnblogs.com/666666A/p/18639544