实验7

任务4

源代码

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

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

    
    fp = fopen(fname, "r");
    if (fp == NULL) {
        perror("fail to open the file to read\n");
        return 0;
    }

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

    --characters;
    
    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

源代码

 

#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) == NULL) {
        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 *fp;
    fp=fopen("D:\\st2_pass.txt","w");
    if(!fp){
        printf("fail to open file\n");
        return;
    }
    fprintf(fp,"%-20s%-20s%-20s%-20s%-30s%-30s\n","准考证号","姓名","客观题得分","操作题得分","总分","结果");
    for(i=0;i<n;++i){
        if(s[i].sum>=60)
            fprintf(fp,"%-20ld\t%-10s\t%-20.2f\t%-20.2f\t%-20.2f\t%-20s\n",s[i].id,s[i].name,s[i].objective,s[i].subjective,s[i].sum,s[i].result);
    }
    fclose(fp);

}
// 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,j=0;
    for(i=0;i<n;++i)
        st[i].sum=st[i].objective+st[i].subjective;
    for(i=0;i<n;++i)
        if(st[i].sum>=60){
            strcpy(st[i].result,"通过");
            st_pass[j]=st[i];
            j+=1;
    }
    else
        strcpy(st[i].result,"未通过");

    return j;
}

 

 

任务6

源代码

 

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

typedef struct{
    long id;
    char name[20];
    char class[20];
}STU;

void read(STU st[]){
    FILE *fp;
    fp = fopen("list.txt", "r");
    if(fp == NULL){
        printf("fail to open the file\n");
        return;
    }
    
    int i, number;
    while(!feof(fp)){
        for(i = 0; i < 80; i++){
            number = fscanf(fp, "%ld %s %s", &st[i].id, st[i].name, st[i].class);
            if(number != 3)
                break;
        }
    }
    fclose(fp);
}

int main(){
    int i,temp,count = 0;
    int choice[5];
    char s[50];
    STU st[80];
    
    read(st);
    
    srand(time(NULL));
    while(count < 5)
    {
        int sign = 1;
        temp = rand() % 80;
        for(i = 0;i<count;i++)
        {
            if(count == choice[i])
            {
                sign=0;
                break;
            }
        }
        if(sign != 0)
        {
            choice[i]=temp;
            count++;
        }
    }
    
    printf("------------随机抽点名单------------\n");
    for (i = 0; i < 5; i++) {
        printf("%ld %-6s %s\n", st[choice[i]].id, st[choice[i]].name, st[choice[i]].class);
    }
    printf("------------保存到文件------------\n输入文件名：");
    scanf("%s", s);
    char list[100];
    strcat(list, "D:\\");
    strcat(list, s);
    FILE *fp = fopen(list, "w");
    if (fp == NULL) {
        printf("fail to open file \n");
        return;
    }
    for (i = 0; i < 5; i++) {
        fprintf(fp, "%ld %-6s %s\n", st[choice[i]].id, st[choice[i]].name, st[choice[i]].class);
    }
    fclose(fp);
    printf("保存成功！\n");
    return 0;    
}