实验7

实验任务4

#include <stdio.h>
#include <stdlib.h>
int main()
{
    FILE *fp1,*fp2,*fp3;
    char ch;
    fp1=fopen("data4.txt","r");
　　fp2=fp3=fp1;
    while((ch=getc(fp2))!=EOF)
    {
        if(ch!=' '&&ch!='\n'&&ch!='\t')
        fp3++;
    }
    printf("data4.txt中共包含%d个字符数",fp3-fp1);
    fclose(fp1);
    return 0;
}

实验任务5

#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;

// 函数声明
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;
}

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

    fin = fopen("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);
}

// 输出考生完整信息: 准考证号，姓名，客观题得分，操作题得分，总分，等级
// 不仅输出到屏幕上，还写到文本文件result.txt中
void output(STU s[], int n) {
    FILE *fout;
    int i;
    
    // 输出到屏幕
    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);
    
    // 保存到文件 
    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);
}

// 对考生信息进行处理：计算总分，排序，确定等级
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;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(i=0;i<n;i++)
    {
        if(i<n*0.1)
            strcpy(s[i].level,"优秀");
        else if(i>=n*0.1&&i<n*0.5)
            strcpy(s[i].level,"合格");
        else
            strcpy(s[i].level,"不合格"); 
    }
    
}

 实验任务6

#include <stdio.h>
#include <time.h>
#define N 30
#define M 100
typedef struct{
    char no[N];
    char name[N];
    char classname[N];
}STU;
int main()
{
    int i=0,flag[M]={0},k;
    STU a[M],b[5];
    FILE *fp,*ptr;
    fp=fopen("list.txt","r");
    ptr=fopen("lucky.txt","w");
    if(fp==NULL)
    {
        printf("fail to open\n");
        return 1;
    }
    if(ptr==NULL)
    {
        printf("fail to open\n");
        return 1;
    }
    while(!feof(fp))
    {
        fscanf(fp,"%s%s%s",a[i].no,a[i].name,a[i].classname);
        i++;
    }
    srand((unsigned)time(NULL));
    for(i=0;i<5;)
    {
        k=rand()%80;
        if(flag[k]==0)
            b[i++]=a[k];
        flag[k]=1;
        
        
    }
    for(i=0;i<5;i++)
    {
        printf("%-30s%-30s%-30s\n",b[i].no,b[i].name,b[i].classname);
        fprintf(ptr,"%-30s%-30s%-30s\n",b[i].no,b[i].name,b[i].classname);
    }
    fclose(fp);
    fclose(ptr);
    return 0;
}