实验7

任务4

实验代码

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

int main(){
    int line=0,len=0;
    char ch;
    FILE *fp;
    
    fp=fopen("data4.txt","r");
    if(!fp){
        printf("fail to open file to read\n");
        return 0;
    }
    while((ch=fgetc(fp))!=EOF){
        if(ch=='\n')
           line++;
        if(ch!=' '&&ch!='\t'&&ch!='\n')
           len+=1;   
    }
    fclose(fp);
    line++;
    
    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",len);
    
    system("pause");
    return 0;
} 

运行结果

任务5

实验代码

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define N 10

typedef struct {
    long id;
    char name[20];
    float objective;
    float subjective;
    float sum;
    char result[10];
} 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;
}


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("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 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;
}


void write(STU st[], int n)
{
    int i;
    FILE *fp;
    fp = fopen("list_pass.txt","w");
    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);
}

运行结果

任务6

实验代码

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

#define STU_NUM 80
#define DRAW_NUM 5

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

void readStu(Student stu[])
{
    FILE* fp;
    int i;
    fp = fopen("list.txt", "r");
    if (fp == NULL)
    {
        printf("list.txt 文件打开失败！\n");
        system("pause");
        exit(1);
    }
    i = 0;
    while (fscanf(fp, "%ld %s %s", &stu[i].id, stu[i].name, stu[i].cls) != EOF && i < STU_NUM)
    {
        i++;
    }
    fclose(fp);
}

int main()
{
    Student allStu[STU_NUM];
    Student winner[DRAW_NUM];
    int flag[STU_NUM] = { 0 };
    int i, count, randIdx;
    char fileName[30];
    FILE* fout;

    count = 0;
    readStu(allStu);

    srand((unsigned)time(NULL));

    while (count < DRAW_NUM)
    {
        randIdx = rand() % STU_NUM;
        if (flag[randIdx] == 0)
        {
            flag[randIdx] = 1;
            winner[count] = allStu[randIdx];
            count++;
        }
    }

    printf("----------中奖名单----------\n");
    for (i = 0; i < DRAW_NUM; i++)
    {
        printf("%ld\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);

    fout = fopen(fileName, "w");
    if (fout == NULL)
    {
        printf("文件创建失败！\n");
        system("pause");
        return 1;
    }
    for (i = 0; i < DRAW_NUM; i++)
    {
        fprintf(fout, "%ld\t%s\t%s\n", winner[i].id, winner[i].name, winner[i].cls);
    }
    fclose(fout);

    printf("保存成功！\n");
    system("pause");
    return 0;
}

运行结果