实验7

任务4

#include <stdio.h>
#include <stdlib.h>

int main() {
    FILE *fp;
    char filename[] = "data4.txt";
    char ch;
    int lines = 0;
    int characters = 0;

    
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("Error opening file");
        return -1;
    }

    
    while ((ch = fgetc(fp))!= EOF) {
        if (ch!= ' ' && ch!= '\n' && ch!= '\t') {
            characters++;
        }
        if (ch == '\n') {
            lines++;
        }
    }

    
    fclose(fp);

    
    printf("data4.txt统计结果:\n");
    printf("行数: %d\n", lines + 1);
    printf("字符数(不计空白符): %d\n", characters);

    return 0;
} 

任务5

#include <stdio.h>
#include <string.h>

#define N 10

typedef struct {
    long id;            // 准考证号
    char name[20];      // 姓名
    float objective;    // 客观题得分
    float subjective;   // 操作题得分
    float sum;          // 总分
    char result[10];    // 考试结果
} STU;

// 函数声明
void read(STU st[], int n);
void write(STU st[], int n);
void output(STU st[], int n);
int process(STU st[], int n, STU st_pass[]);

int main() {
    STU stu[N], stu_pass[N];
    int cnt;
    double pass_rate;

    printf("从文件读入%d个考生信息...\n", N);
    read(stu, N);

    printf("\n对考生成绩进行统计...\n");
    cnt = process(stu, N, stu_pass);

    printf("\n通过考试的名单:\n");
    output(stu, N);   // 输出所有考生完整信息到屏幕
    write(stu, N);    // 输出考试通过的考生信息到文件

    pass_rate = 1.0 * cnt / N;
    printf("\n本次等级考试通过率: %.2f%%\n", pass_rate*100);

    return 0;
}

// 把所有考生完整信息输出到屏幕上
// 准考证号，姓名，客观题得分，操作题得分，总分，结果
void output(STU st[], int n) {
    int i;
    
    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");
    for (i = 0; i < n; i++)
        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);
}

// 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
void read(STU st[], int n) {
    int i;
    FILE *fin;

    fin = fopen("examinee.txt", "r");
    if (!fin) {
        printf("fail to open file\n");
        return;
    }

    while (!feof(fin)) {
        for (i = 0; i < n; i++)
            fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name, &st[i].objective, &st[i].subjective);
    }

    fclose(fin);
}

// 把通过考试的考生完整信息写入文件list_pass.txt
// 准考证号，姓名，客观题得分，操作题得分，总分，结果
void write(STU s[], int n) {
    int i;
    FILE *fout;
    fout = fopen("list_pass.txt","w");
     if (!fout) {
        printf("fail to open file\n");
        return ;
    }
    fprintf(fout, "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");
    for (i = 0; i < n; i++) {
        if (s[i].sum >= 60) {
            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].result);
        }
    }
    fclose(fout);
}

// 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
int process(STU st[], int n, STU st_pass[]) {
    int i, count = 0;
    for (i = 0; i < n; i++) {
        st[i].sum = st[i].objective + st[i].subjective;
        if (st[i].sum >= 60) {
            st_pass[count] = st[i];
            strcpy(st[i].result, "通过");
            count++;
        } else {
            strcpy(st[i].result, "未通过");
        }
    }
    return count;
}

任务6

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#define MAX_STU 80
#define MAX_LENGTH 100
#define selectCount 5

typedef struct {
    char id[20];        // 学号
    char name[20];      // 姓名
    char className[20]; // 班级
} Student;

void read(const char *fileName, Student students[],int *sum) {
    FILE *fp = fopen(fileName, "r");
    int number, cnt=0;
    if (fp == NULL) {
        printf("无法打开文件\n");
        return;
    }

    char line[MAX_LENGTH];
    while (!feof(fp)) {
        number=fscanf(fp, "%s %s %s", students[cnt].id, students[cnt].name, students[cnt].className);
        if(number!=3)
        {
            break;
        }
        cnt++;
    }
    *sum=cnt;
    fclose(fp);
}

void random_stu(Student students[],Student selected[],int sum) {
    srand(time(NULL));
    for (int i = sum - 1; i > 0; i--) {
        int j = rand() % (i + 1);
        Student temp = students[i];
        students[i] = students[j];
        students[j] = temp;
    }
    for(int i=0;i<selectCount;i++)
    {
        selected[i]=students[i];
    }  
}

void sort(Student selected[], int cnt) {
    for (int i = 0; i < cnt - 1; i++) {
        for (int j = 0; j < cnt - i - 1; j++) {
            if (strcmp(selected[j].id, selected[j + 1].id) > 0) {
                Student t = selected[j];
                selected[j] = selected[j + 1];
                selected[j + 1] = t;
            }
        }
    }
}

void save(const char *fileName, Student selected[], int cnt) {
    FILE *fp = fopen(fileName, "w");
    if (fp == NULL) {
        printf("无法创建文件\n");
        return;
    }

    for (int i = 0; i < cnt; i++) {
        fprintf(fp, "%s %s %s\n", selected[i].id, selected[i].name, selected[i].className);
    }

    fclose(fp);
    printf("文件保存成功!\n");
}

int main() {
    const char *FileName = "list.txt";
    Student students[MAX_STU], selected[selectCount];
    int sum;


    read(FileName, students,&sum);

    random_stu(students, selected, sum); 

    printf("---------随机抽取的学生名单---------\n");
    for (int i = 0; i < selectCount; i++) {
        printf("%s %s %s\n", selected[i].id, selected[i].name, selected[i].className);
    }

    sort(selected, selectCount);

    char outputFileName[50];
    time_t t = time(NULL);
    struct tm *tmInfo = localtime(&t);
    strftime(outputFileName, sizeof(outputFileName), "%Y%m%d.txt", tmInfo);

    save(outputFileName, selected, selectCount);

    return 0;
}