实验7

任务4

源代码

#include<stdio.h>
int read1(){
    int count=0;
    
    FILE *fp;
    fp=fopen("datal4.txt","r");
    
    if(fp==NULL){
        printf("fail to open file to read \n");
        return 0;
    }
    
    char c;
    
    while(!feof(fp)){
        c=fgetc(fp);
        if(c!=' '&&c!='\n'&&c!='\t'){
            count++;
        } 
    } 
    fclose(fp);
    return count;
} 
int read2(){
    int i;
    int line=0;
    
    FILE *fp;
    fp=fopen("datal4.txt","r");
    
    if(fp==NULL){
        printf("fail to open file to read \n");
        return 0;
    }
    
    char c;
    
    while(!feof(fp)){
        c=fgetc(fp);
        if(c=='\n'){
            line++;
        } 
    } 
    if(c!='\n'&&line==0){
        line=1;
    }
    fclose(fp); 
    return line;
} 
int main(){
    
    printf("datal4.txt统计结果:\n");
    
    printf("行数:%-20d\n",read2());
    
    printf("字符数(不计空白符):%-20d\n",read1());
    
    return 0;
}

结果

 任务5

源代码

#include<stdio.h>
#include<string.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...\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);
    write(stu,N);
    
    
    pass_rate=1.0*cnt/N;
    printf("\n本次等级考试通过率:%.2f%%\n",pass_rate*100);
    
    return 0;
}

void read(STU st[],int n){
    int i;
    FILE *fp;
    fp=fopen("examinee.txt","r");
    if(!fp){
        printf("fail to open file \n");
        return ;
    }
    
    while(!feof(fp)){
        for(i=0;i<n;i++)
            fscanf(fp,"%ld %s %f %f",&st[i].id,st[i].name,
                    &st[i].objective,&st[i].subjective);
    } 
    fclose(fp);
}

void write(STU st[],int n){
    int i;
    
    FILE *fp;
    
    fp=fopen("list_pass.txt","w");
    if(!fp){
        printf("fail to open file \n");
        return ;
    }
    
    for(i=0;i<n;i++)
        if(st[i].objective+st[i].subjective>=60)
            fprintf(fp,"%1d\t\t%8s\t\t%.2f\t\t%.2f\t\t%.2f\t\t%-15s \n",
            st[i].id,st[i].name,st[i].objective,st[i].subjective,
                st[i].sum,st[i].result);
                
    fclose(fp);
}
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("%1d\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%-15s\n",
                st[i].id,st[i].name,
                st[i].objective,st[i].subjective,
                st[i].sum,st[i].result);    
    
}
int process(STU st[],int n,STU st_pass[]){
    int i,count=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");
            count++;
        }
        else
            strcpy(st[i].result,"不通过"); 
    }
    return count;
}

结果

 任务7

源代码

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

#define N 100

typedef struct{
    long id;
    char name[20];
    char class1[N];
}stu;

stu st[N];

int read();
void output();

int main(){
    printf("---------随机抽点名单---------\n");
    if(read()==0)
        return 1;
    
    printf("----------保存到文件-----------\n");
    int count=read();
    output(st,count);
    printf("保存成功!"); 
    
    return 0;
}
int  read(){
    int i=0,j,n;
    int number=0;
    
    FILE *fp;
    fp=fopen("list.txt","r");
    
    if(fp==NULL){
        printf("fail to open file to read \n");
        return;
    }
    
    i = 0;
    while(!feof(fp)) {
        number = fscanf(fp,"%19ld %19s %49s",&st[i].id,st[i].name,st[i].class1);
        if(number !=3)
            break;
        i++;
    }
    n = i;
    
    
    for(j=0;j<i;j++){
        printf("%19ld %19s %49s\n",st[j].id,st[j].name,st[j].class1);
    }
    
    
    return i;
}
void output(const stu s[],int n){
    int i,j;
    
    srand(time(NULL));
    
    stu t[N];
    
    
    for(i=n-1;i>0;i--){
        int j=rand()%(i+1);
        stu t=st[i];
        st[i]=st[j];
        st[j]=t;
    }
    
    char txt[N];
    
    printf("请输入文件名:");
    scanf("%s",txt);
    
    FILE *fp2=fopen(txt,"w");
    
    if(fp2==NULL){
        printf("无法创建文件");
        return ; 
    }
    
    for(i=0;i<5&&i<n;i++){
        fprintf(fp2,"%19ld %19s %49s\n",st[i].id,st[i].name,st[i].class1);
        printf("%19ld %19s %49s\n",st[i].id,st[i].name,st[i].class1);
    }
    
    fclose(fp2);
} 

结果