实验七

任务4：

#include <stdio.h>
#define N 10
#define M 100

int main(){
    char t,x[N][M];
    int i,j,line=0,s=0;
    FILE *fp;
    
    fp=fopen("data4.txt","r");
    if(fp==NULL){
        printf("fail to open file to read\n");
        return;
    }
    
    for(i=0;i<N;i++){
        if(fgets(x[i],M,fp)!=NULL)
           line++;
    }
    
    for(i=0;i<line;i++){
        j = 0;
        while(x[i][j]!='\0'){
            t=x[i][j];
            
            if(t!=' '&&t!='\n'&&t!='\r')
               s++;
               
            j++;
        }
    }
    
    fclose(fp);
    
    printf("data4.txt统计结果：\n");
    printf("行数：%20d\n",line);
    printf("字符数（不计空白符）：%5d",s);
    
    return 0;
} 

任务5：

#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 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;
    }
    
    while(!feof(fin)){
        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);
}

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;
    }
    
    fprintf(fp,"准考证号        姓名         客观题得分       操作题得分      总分      结果\n"); 
    for(i=0;i<n;i++){
        if(st[i].sum>=60){
         fprintf(fp,"%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);
        } 
    }
    
    fclose(fp);
}

int process(STU st[],int n,STU st_pass[]){
    int i,j;
    int 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");
            st_pass[count++]=st[i]; 
        }
        else
            strcpy(st[i].result,"未通过"); 
    }
    
    return count;
}

                        

任务6：

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define N 80

typedef struct {
    char id[10];
    char name[20];
    char class[20];
}STU;

int main(){
    STU st[N];
    int i;
    FILE *fp1;
    
    fp1 = fopen("list.txt","r");
    if(!fp1){
        printf("fail to open file\n");
        return;                                       
    }
    
    while(!feof(fp1)){
        for(i = 0;i < N;i++)
        fscanf(fp1,"%s %s %s",st[i].id,st[i].name,st[i].class);
    }
    
    fclose(fp1);
    
    int x[5];   
    int j,k=0;
    
    srand(time(NULL));
    for(i = 0;i < 5;i++){
        x[i] = rand()%80 + 1;
        for(j = 0;j < i;j++){
            if(x[j]==x[i]){
                i--;
                continue;
            }
        }
    }
    
    char t[N];
    
    printf("---------------随机抽点名单---------------\n");
    for(i = 0;i < 5;i++)
    printf("%-20s%-10s%-10s\n",st[x[i]].id,st[x[i]].name,st[x[i]].class);
    printf("----------保存到文件----------\n");
    printf("输入文件名：");
    scanf("%s",t);
    FILE *fp2;
    
    fp2 = fopen(t,"w");
    if(!fp2){
        printf("fail to open file\n");
        return;
    }
    
    for(i = 0;i < 5;i++)
        fprintf(fp2,"%-20s%-10s%-10s\n",st[x[i]].id,st[x[i]].name,st[x[i]].class);
        
    fclose(fp2);
    
    printf("保存成功！");
    return 0;
}