实验7

任务4

源代码

#include <stdio.h>
int main()
{FILE*fp=fopen("C:\\Users\\27367\\Downloads\\实验7数据文件及部分代码_gbk\\实验7数据文件及部分代码_gbk\\data4.txt","r");
if(fp=NULL)
{perror("open file failed");
return 1;
}
char ch;
int line=0;
int char_cnt=0;
int newline=1;
while((ch=fgetc(fp))!=EOF)
{if(ch=='\n')
{line++;
newline=1;
continue;
}
if(ch==' '||ch=='\t')
continue;
char_cnt++;
newline=0;
}
if(!newline)
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）：%d\n",char_cnt);
return 0;
 } 

运行结果

任务5

源代码

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

#define MAX_N 100

typedef struct
{
    char id[20];    
    char name[20];  
    int obj;        
    int op;         
    int total;      
    char res[10];   
} STU;


void read(STU st[], int n)
{
    FILE *fp = fopen("examinee.txt", "r");
    if (fp == NULL)
    {
        perror("open examinee.txt error");
        return;
    }
    int i = 0;
    while (i < n && fscanf(fp, "%s %s %d %d", st[i].id, st[i].name, &st[i].obj, &st[i].op) == 4)
    {
        i++;
    }
    fclose(fp);
}


int process(STU st[], int n, STU st_pass[])
{
    int pass_cnt = 0;
    for (int i = 0; i < n; i++)
    {
        st[i].total = st[i].obj + st[i].op;
        if (st[i].total >= 60)
        {
            strcpy(st[i].res, "通过");
            st_pass[pass_cnt++] = st[i];
        }
        else
        {
            strcpy(st[i].res, "未通过");
        }
    }
    return pass_cnt;
}


void write(STU st_pass[], int pass_num)
{
    FILE *fp = fopen("list_pass.txt", "w");
    if (fp == NULL)
    {
        perror("open list_pass.txt error");
        return;
    }
    fprintf(fp, "准考证号\t姓名\t客观题\t操作题\t总分\t结果\n");
    for (int i = 0; i < pass_num; i++)
    {
        fprintf(fp, "%s\t%s\t%d\t%d\t%d\t%s\n",
                st_pass[i].id, st_pass[i].name,
                st_pass[i].obj, st_pass[i].op,
                st_pass[i].total, st_pass[i].res);
    }
    fclose(fp);
}


void output(STU st_pass[], int pass_num)
{
    printf("===== 通过考试考生信息 =====\n");
    printf("准考证号\t姓名\t客观题\t操作题\t总分\n");
    for (int i = 0; i < pass_num; i++)
    {
        printf("%s\t%s\t%d\t%d\t%d\n",
               st_pass[i].id, st_pass[i].name,
               st_pass[i].obj, st_pass[i].op, st_pass[i].total);
    }
}

int main(void)
{
    STU stu[MAX_N];
    STU pass_stu[MAX_N];
    int total_stu = 3;
    read(stu, total_stu);
    int pass = process(stu, total_stu, pass_stu);
    write(pass_stu, pass);
    output(pass_stu, pass);
    double rate = (double)pass / total_stu * 100;
    printf("\n本次考试通过率：%.2f%%\n", rate);
    return 0;
}

 运行结果

任务6

源代码

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

#define N 80

typedef struct {
    char id[15];
    char name[20];
    char cls[30];
} Student;

int main() {
    Student s[N], lucky[5];
    int flag[N] = {0};
    FILE *fp;
    int i, n = 0;
    int cnt = 0;
    char fname[50];

    fp = fopen("list.txt", "r");
    if (fp == NULL) {
        printf("无法打开 list.txt\n");
        return 1;
    }

    while (fscanf(fp, "%s%s%[^\n]", s[n].id, s[n].name, s[n].cls) != EOF) {
        n++;
    }
    fclose(fp);

    srand(time(NULL));

    while (cnt < 5) {
        int r = rand() % n;
        if (flag[r] == 0) {
            lucky[cnt] = s[r];
            flag[r] = 1;
            cnt++;
        }
    }

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

    printf("保存到文件\n");
    printf("输入文件名：");
    scanf("%s", fname);

    fp = fopen(fname, "w");
    if (fp == NULL) {
        printf("文件保存失败\n");
        return 1;
    }

    for (i = 0; i < 5; i++) {
        fprintf(fp, "%s %s %s\n", lucky[i].id, lucky[i].name, lucky[i].cls);
    }
    fclose(fp);

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

运行结果