实验七

task4

#include<stdio.h>
int func(){
    int ans,i;
    char c;
    FILE *fp;
    fp=fopen("data4.txt","r");
    
    while(fp==NULL){
    printf("fail to open file\n");
    return 0;}

    i = 0;
    while(!feof(fp)) {
        c=fgetc(fp);
        if(c!=' '&&c!='\n')
        i++;
    }
        fclose(fp);
    ans = i - 1;
        return ans;

}
int main(){
    int ans;
    ans=func();
    
    if(ans!=0)
    printf("date4.txt中共包含字符数（不计空白符）：%d",ans);
    
return 0;
}

task5

#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;          // 总分
    char ans[10];       // 考试结果
} STU;

// 函数声明
void finput(STU st[], int n);
void foutput(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);
    finput(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_pass, cnt);      // 输出到屏幕
    foutput(stu_pass, cnt);    // 输出到文件

    pass_rate = 1.0 * cnt / N;
    printf("\n本次等级考试通过率: %.2f%%\n", pass_rate*100);

    return 0;
}

// 把通过考试的考生完整信息输出到屏幕上
// 准考证号，姓名，客观题得分，操作题得分，总分，结果
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].ans);
}

// 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 finput(STU st[], 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", &st[i].id, st[i].name, &st[i].objective, &st[i].subjective);
    }

    fclose(fin);
}

// 把通过考试的考生完整信息写入文件list_pass.txt
// 准考证号，姓名，客观题得分，操作题得分，总分，结果
void foutput(STU s[], int n) {
    FILE *fout;
    int i;
    
    // 保存到文件 
    fout = fopen("list_pass.txt", "w");
    if (!fout) {
        printf("fail to open or create list_pass.txt\n");
        exit(0);
    }
    
    fprintf(fout, "准考证号\t\t姓名\t\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++)
        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].ans);

    fclose(fout);
}

// 对考生信息进行处理：计算每位考生考试总分、结果；统计考试通过的人数
int process(STU st[], int n, STU st_pass[]) {
   int i,j;
   for(i=0,j=0;i<n;++i){
   st[i].sum=st[i].objective+st[i].subjective;
   if(st[i].sum>=60){
   strcpy(st[i].ans,"pass");
   st_pass[j++]=st[i];}
   else
   strcpy(st[i].ans,"fail");}
   return j;
}

task6

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define N 100
struct STU {
    long int id;
    char name[N];
    char cla[N];
} st[N], lucky[N];

void func1(void);
int func2(void);
void func3(void);
int main() {
    int j, n;
    func1();
    srand((unsigned)time(NULL));
    for (j = 0; j < 5; j++) {
        n = func2();
        lucky[j] = st[n];
        printf("%ld\t %s\t %s\t\n", lucky[j].id, lucky[j].name, lucky[j].cla);
    }
    func3();
    getchar();
    return 0;
}
void func1(void) {
    int i;
    FILE *fp;
    fp = fopen("list.txt", "r");
    if (fp == NULL) {
        printf("Failed to open file\n");
        return;
    }
    i = 0;
    while (fscanf(fp, "%ld %s %s", &st[i].id, st[i].name, st[i].cla) == 3 && i < N) {
        ++i;
    }
    fclose(fp);
}
int func2(void) {
    return rand() % 80;
}
void func3(void) {
    int j;
    FILE *fout;
    fout = fopen("lucky.txt", "w");
    if (fout == NULL) {
        printf("Failed to open file\n");
        return;
    }
    for (j = 0; j < 5; j++) {
        fprintf(fout, "%ld\t %s\t %s\t\n", lucky[j].id, lucky[j].name, lucky[j].cla);
    }
    fclose(fout);
}