实验七

task4.c

#include <stdio.h>

int main()
{
    FILE *fp;
    int ch;
    int line = 0;
    int char_cnt = 0;
    int has_content = 0; 

    fp = fopen("data4.txt", "r");
    if(fp == NULL)
    {
        printf("打开文件失败\n");
        return 1;
    }

    while((ch = fgetc(fp)) != EOF)
    {
        has_content = 1;
        if(ch == ' ' || ch == '\n' || ch == '\t')
        {
            if(ch == '\n')
                line++;
            continue;
        }
        char_cnt++;
    }

    if(has_content)
        line++;

    fclose(fp);

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

    return 0;
}

 

 task5.c

#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: 已完成\n", N);
    read(stu, N);

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

    printf("\n所有考生完整信息:\n");
    output(stu, N);   

    printf("\n通过考试的名单写入文件: 已完成!\n");
    write(stu_pass, cnt);

    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;
    }

    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);
}

// 对考生信息进行处理：计算每位考生考试总分、结果；统计并返回通过考试的人数
int process(STU st[], int n, STU st_pass[]) {
    int i, cnt = 0;
    for(i = 0; i < n; i++)
    {
        st[i].sum = st[i].objective + st[i].subjective;
        if(st[i].sum >= 60)
        {
            strcpy(st[i].result, "通过");
            st_pass[cnt] = st[i];
            cnt++;
        }
        else
        {
            strcpy(st[i].result, "不通过");
        }
    }
    return cnt;
}

// 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 st[], int n) {
    FILE *fp;
    int i;
    fp = fopen("list_pass.txt", "w");
    if(!fp)
    {
        printf("fail to open write file\n");
        return;
    }
    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");
    for(i = 0; i < n; i++)
    {
        fprintf(fp,"%ld\t%s\t%.2f\t%.2f\t%.2f\t%s\n",
        st[i].id, st[i].name, st[i].objective, st[i].subjective, st[i].sum, st[i].result);
    }
    fclose(fp);
}

 task6.c

必做：

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

#define N 80
#define WIN 5

typedef struct {
    char id[20];
    char name[20];
    char cls[30];
} Stu;

int main()
{
    Stu all[N];
    int flag[N] = {0}; 
    Stu winner[WIN];
    int i, cnt = 0, rnd;
    char filename[50];
    FILE *fp;

   
    fp = fopen("list.txt", "r");
    if (!fp)
    {
        printf("打开list.txt失败\n");
        return 1;
    }
    for (i = 0; i < N; i++)
    {
        fscanf(fp, "%s %s %s", all[i].id, all[i].name, all[i].cls);
    }
    fclose(fp);

    
    srand((unsigned)time(NULL));
    while (cnt < WIN)
    {
        rnd = rand() % N;
        if (flag[rnd] == 0)
        {
            flag[rnd] = 1;
            winner[cnt++] = all[rnd];
        }
    }

    
    printf("----------------中奖名单----------------\n");
    for (i = 0; i < WIN; i++)
    {
        printf("%s\t%s\t%s\n", winner[i].id, winner[i].name, winner[i].cls);
    }
    printf("----------------保存到文件----------------\n");

  
    printf("输入文件名：");
    scanf("%s", filename);
    fp = fopen(filename, "w");
    for (i = 0; i < WIN; i++)
    {
        fprintf(fp, "%s\t%s\t%s\n", winner[i].id, winner[i].name, winner[i].cls);
    }
    fclose(fp);
    printf("保存成功!\n");

    return 0;
}

 选做：

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

#define N 80
#define WIN 5

typedef struct {
    char id[20];
    char name[20];
    char cls[30];
} Stu;

// 按学号升序排序
void sortStu(Stu arr[], int n)
{
    int i, j;
    Stu tmp;
    for (i = 0; i < n - 1; i++)
    {
        for (j = 0; j < n - i - 1; j++)
        {
            if (strcmp(arr[j].id, arr[j+1].id) > 0)
            {
                tmp = arr[j];
                arr[j] = arr[j+1];
                arr[j+1] = tmp;
            }
        }
    }
}

int main()
{
    Stu all[N];
    int flag[N] = {0};
    Stu winner[WIN];
    int i, cnt = 0, rnd;
    char filename[50];
    FILE *fp;
    time_t now = time(NULL);
    struct tm *t = localtime(&now);


    strftime(filename, sizeof(filename), "%Y%m%d.txt", t);

  
    fp = fopen("list.txt", "r");
    if (!fp)
    {
        printf("打开list.txt失败\n");
        return 1;
    }
    for (i = 0; i < N; i++)
    {
        fscanf(fp, "%s %s %s", all[i].id, all[i].name, all[i].cls);
    }
    fclose(fp);


    srand((unsigned)time(NULL));
    while (cnt < WIN)
    {
        rnd = rand() % N;
        if (flag[rnd] == 0)
        {
            flag[rnd] = 1;
            winner[cnt++] = all[rnd];
        }
    }


    sortStu(winner, WIN);


    printf("----------------%s中奖名单----------------\n", filename);
    for (i = 0; i < WIN; i++)
    {
        printf("%s\t%s\t%s\n", winner[i].id, winner[i].name, winner[i].cls);
    }

  
    fp = fopen(filename, "w");
    for (i = 0; i < WIN; i++)
    {
        fprintf(fp, "%s\t%s\t%s\n", winner[i].id, winner[i].name, winner[i].cls);
    }
    fclose(fp);
    printf("文件保存成功!\n");

    return 0;
}