实验7 文件应用编程

task4

 

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define N 1000

int main() {
    char x[N];
    char s[N];
    int i=0;
    int line = 0;
    int count = 0;
    FILE* fp;
    fp = fopen("C:\\task7\\task7\\data4.txt", "r");

    if (fp == NULL) {
        printf("fail to open file to read\n");
    }

    printf("data4.txt统计结果：\n");

    while (fgets(x, sizeof(x), fp) != NULL)
        line++;
    printf("行数：%d\n", line);

    while (!feof(fp)) {
        s[i]=fgetc(fp);
        if (s[i] != ' ' && s[i] != '\n')
            count++;

    }
    
    printf("字符数（不含空白符）:%d\n", count);

    fclose(fp);

    system("pause");
    return 0;
}

 

 

task5

#define _CRT_SECURE_NO_WARNINGS
#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("C:\\task7\\task7\\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* fp;

    fp = fopen("C:\\task7\\task7\\list_pass.txt","w");
    if (!fp) {
        printf("fail to open file\n");
        return;
    }
    fprintf(fp, "%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", "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(fp,"%ld %s %f %f %.2f %s\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;
    int k = 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");
        else
            strcpy(st[i].result, "不通过");
    }
    for (i = 0;i < n;++i) {
        if (st[i].sum >= 60) {
            st_pass[k] = st[i];
            k++;
        }
        
    }
    return k;
}

 

task6

 

#define _CRT_SECURE_NO_WARNINGS
#include<stdlib.h>
#include<stdio.h>
#include<time.h>
#define N 80

typedef  struct{
    char id[20];
    char name[20];
    char classes[20];
}list;
int main(){
    list st[N];
    int num;
    int i=0,j;
    int x[5];
    int choose;
    int flag=0;
    char filename[20];

    FILE*fp1;
    FILE*fp2;
    fp1=fopen("C:\\task7\\task7\\list.txt","r");
    if(fp1==NULL){
        printf("fail to open the file to read\n");
        return;
    }
    while(!feof(fp1)){
        num=fscanf(fp1,"%s %s %s\n",st[i].id,st[i].name,st[i].classes);
        if(num!=3)
            break;
        i++;
    }

    srand(time(NULL));
    for(i=0;i<5;){
        choose=rand()%80;
        for(j=0;j<5;++j){
            if(x[j]==choose){
                flag=1;
                break;
            }
        }
        if(flag==0){
            x[i]=choose;
            i++;
        }
    }
    fclose(fp1);

    printf("随机抽点名单\n");
    for(i=0;i<5;++i){
        printf("%s %s %s\n",st[x[i]].id,st[x[i]].name,st[x[i]].classes);
    }
    printf("保存到文件\n");
    printf("输入文件名:");
    scanf("%s",filename);
    fp2=fopen(filename,"w");
    if(fp2==NULL){
        printf("fail to open file to write\n");
        return;
    }
    for(i=0;i<5;++i){
        fprintf(fp2,"%s %s %s\n",st[x[i]].id,st[x[i]].name,st[x[i]].classes);
    }
    printf("保存成功");
    fclose(fp2);

    system("pause");
    return 0;
}