实验六 文件应用编程

实验任务4

#define _CRT_SECURE_NO_WARNINGS
#include<stdlib.h>
#include<stdio.h>
int main() {
    char ch;
    int count = 0;
    FILE* fp;
    fp = fopen("data4.txt", "r");
    if (fp == NULL)
    {
        printf("F://fail to open file");
        return 1;
    }
    ch = fgetc(fp);
    while (ch != EOF)
    {

        if (ch != ' ' && ch != '\n')
            count++;
        ch = fgetc(fp);
    }
    printf("data4.txt中共包含字符数（不计空白符）: %d", count);
    fclose(fp);
    system("pause");
    return 0;
}

实验任务5

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

#define N 10

typedef struct {
    long int id;
    char name[20];
    float objective;    // 客观题得分
    float subjective;   // 操作题得分
    float sum;
    char level[10];
} STU;

void input(STU s[], int n);
void output(STU s[], int n);
void process(STU s[], int n);

int main() {
    STU stu[N];

    printf("从文件读入%d个考生信息: 准考证号，姓名，客观题得分(<=40)，操作题得分(<=60)\n", N);
    input(stu, N);

    printf("\n对考生信息进行处理: 计算总分，确定等级\n");
    process(stu, N);

    printf("\n打印考生完整信息, 并保存到文件中");
    output(stu, N);

    return 0;
}

void input(STU s[], int n) {
    int i;
    FILE* fin;

    fin = fopen("F://examinee.txt", "r");
    if (fin == NULL) {
        printf("fail to open file\n");
        exit(0);
    }

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

    fclose(fin);
}

void output(STU s[], int n) {
    FILE* fout;
    int i;
    printf("\n");
    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等级\n");
    for (i = 0; i < n; i++)
        printf("%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].level);
    fout = fopen("result.txt", "w");
    if (!fout) {
        printf("fail to open or create result.txt\n");
        exit(0);
    }

    fprintf(fout, "准考证号\t\t姓名\t客观题得分\t操作题得分\t总分\t\t等级\n");

    for (i = 0; i < n; i++)
        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].level);

    fclose(fout);
}

void process(STU s[], int n) {
    int i, j;
    STU t;
    for (i = 0; i < n; i++)
    {
        s[i].sum = s[i].objective + s[i].subjective;
    }


    for (i = 0; i < n - 1; i++)
    {
        for (j = 0; j < n - 1 - i; j++)
            if (s[j].sum < s[j + 1].sum)
            {
                t = s[j];
                s[j] = s[j + 1];
                s[j + 1] = t;
            }
    }
    for (int i = 0; i < n; i++)
        if (i + 1 <= n * 0.1)
            strcpy(s[i].level, "优秀");
        else if (i + 1 >= n * 0.1 && i + 1 <= n * 0.5)
            strcpy(s[i].level, "合格");
        else
            strcpy(s[i].level, "不合格");
}

实验任务6

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

typedef struct
{
    long int no;
    char name[20];
    char clas[100];
} STU;


int main()
{
    int i, j;
    STU x[80];
    STU lucky[5];
    FILE* fp;
    fp = fopen("F://list.txt", "r");

    if (fp == NULL)
    {
        printf("fail to open file\n");
        return 1;
    }

    while (!feof(fp))
    {
        for (i = 0; i < 80; i++)
            fscanf(fp, "%ld%s%s", &x[i].no, x[i].name, x[i].clas);
    }
    fclose(fp);

    FILE* fp2;

    fp2 = fopen("F://lucky.txt", "w");
    if (fp2 == NULL)
    {
        printf("fail to open file\n");
        return 1;
    }

    srand(time(NULL));
    for (i = 0; i < 5; i++)
        lucky[i].no = 204942000 + rand() % 80 + 1;

    for (i = 0; i < 5; i++)
    {
        for (j = 0; j < 80; j++)
        {
            if (lucky[i].no == x[j].no)
                lucky[i] = x[j];
        }
    }

    for (i = 0; i < 5; ++i)
    {
        fprintf(fp2, "%ld\t%s\t%s\n", lucky[i].no, lucky[i].name, lucky[i].clas);
        printf("%ld\t%s\t%s\n", lucky[i].no, lucky[i].name, lucky[i].clas);
    }

    fclose(fp2);

    return 0;
}