实验七

task4

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <stdlib.h>

int main() {
    FILE *fp = fopen("data4.txt", "r");
    if (fp == NULL) {
        printf("打开文件失败！\n");
        system("pause");
        return 1;
    }
    int ch;
    int line = 0;
    int charCnt = 0;
    int flagNewline = 1; 

    while ((ch = fgetc(fp)) != EOF) {
    
        if (ch == '\n') {
            line++;
            flagNewline = 1;
        }
    
        else if (ch == ' ' || ch == '\t' || ch == '\r') {
            continue;
        } else {
            charCnt++;
            flagNewline = 0;
        }
    }
    
    if (!flagNewline) 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", charCnt);

    system("pause");
    return 0;
}

 task5：#define _CRT_SECURE_NO_WARNINGS 1

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

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);

    system("pause");
    return 0;
}

//打印全部学生
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);
}

void read(STU st[], int n) {
    int i;
    FILE *fin;
    fin = fopen("D:\新建文件夹\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);
}

int process(STU st[], int n, STU st_pass[]) {
    int passNum = 0;
    for (int 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[passNum++] = st[i];
        } else {
            strcpy(st[i].result, "未通过");
        }
    }
    return passNum;
}

//【补全】写入合格名单 list_pass.txt
void write(STU st[], int n) {
    FILE *fp = fopen("list_pass.txt", "w");
    if (fp == NULL) {
        printf("打开输出文件失败\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\t结果\n");
    for (int i = 0; i < n; i++) {
        fprintf(fp, "%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);
    }
    fclose(fp);
}

 

 

task6:

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#define MAX_STU 80

typedef struct {
    char id[20];
    char name[20];
    char cls[40];
} Student;

int main() {
    FILE *fp = fopen("list.txt", "r");
    if (!fp) {
        printf("无法打开list.txt\n");
        system("pause");
        return 1;
    }
    Student stu[MAX_STU];
    int total = 0;
    //读取全部学生
    while (fscanf(fp, "%s %s %[^\n]", stu[total].id, stu[total].name, stu[total].cls) == 3) {
        total++;
    }
    fclose(fp);

    int flag[MAX_STU] = {0}; //标记是否抽中
    Student lucky[5];
    srand((unsigned)time(NULL));

    //抽取5个不重复
    int cnt = 0;
    while (cnt < 5) {
        int r = rand() % total;
        if (flag[r] == 0) {
            flag[r] = 1;
            lucky[cnt++] = stu[r];
        }
    }

    //屏幕输出中奖名单
    printf("=====中奖名单=====\n");
    for (int i = 0; i < 5; i++) {
        printf("%s %s %s\n", lucky[i].id, lucky[i].name, lucky[i].cls);
    }

    //输入文件名保存
    char fileName[50];
    printf("\n输入保存文件名：");
    scanf("%s", fileName);
    FILE *fw = fopen(fileName, "w");
    if (!fw) {
        printf("文件创建失败\n");
        system("pause");
        return 1;
    }
    for (int i = 0; i < 5; i++) {
        fprintf(fw, "%s %s %s\n", lucky[i].id, lucky[i].name, lucky[i].cls);
    }
    fclose(fw);
    printf("保存成功！\n");

    system("pause");
    return 0;
}