NUIST 《程序设计基础》 实验7

第七次实验课~

Task 4

<task4.c>

源代码

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#include <stdio.h>

int main() {
    FILE *data4;

    data4 = fopen("data4.txt", "r");
    if(!data4) { printf("Open file failed.(data4.txt)"); return 1; }

    int ch, lines=0, chars=0;
    while(~(ch = fgetc(data4))) {/*
        if(ch == "\n") lines++;
        if(ch >= 'A' && ch <= 'z') chars++;*/

        switch (ch) {
        case ' ':
        case '\r':
        case '\t':
            break;

        case '\n':
            lines++;
            break;
        
        default:
            chars++;
            break;
        }
    }
    lines++;
    fclose(data4);
    printf("data4.txt统计结果: \n行数: %d\n字符数(不计空白符): %d", lines, chars);
}

运行结果

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Task 5

<task5.c>

源代码

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

#define N 10

typedef struct {
    long id;            // 准考证号
    char name[20];      // 姓名
    float objective;    // 客观题得分
    float subjective;   // 操作题得分
    float sum;          // 总分
    char result[10];    // 考试结果
} STU;

// 函数声明
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);   // 输出所有考生完整信息到屏幕
    write(stu_pass, cnt);    // 输出考试通过的考生信息到文件

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

    return 0;
}

// 把所有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].result);
}

// 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 read(STU st[], int n) {
    int i;
    FILE *fin;

    fin = fopen("examinee.txt", "r");
    if (!fin) {
        printf("fail to open file\n");
        return;
    }

    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 write(STU s[], int n) {
    FILE *passtxt;
    passtxt = fopen("list_pass.txt", "w");
    if (!passtxt) {
        printf("Open file failed(list_pass.txt)");
        return 1;
    }

    fprintf(passtxt, "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 (int i = 0; i < n; i++) {
        fprintf(passtxt, "%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].result);
    }

    fclose(passtxt);
}

// 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 j=0;
    for(int i=0; i<n; i++) {
        st[i].sum = st[i].objective + st[i].subjective;
        strcpy(st[i].result, st[i].sum > 60 ? "通过" : "未通过");
        if(st[i].sum > 60)
            st_pass[j++] = st[i];
    }
    return j;
}

运行结果

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Task 6

<task6.c>

源代码

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

typedef struct {
    long long xh;
    char name[50];
    char class[50];
} stu;

int read(stu list[]) {
    FILE *stulist;
    int n=0;

    stulist = fopen("list.txt", "r");
    if(!stulist) {
        printf("list.txt open failed");
        return 1;
    }

    while (~fscanf(stulist, "%lld %s %s", &list[n].xh, list[n].name, list[n].class)) n++;

    return n;
}

void bubblesort(stu win[100]) {
    for (int i = 0; i < 4; i++) {
        int swapped = 0;
        for (int j = 0; j < 5 - i - 1; j++) {
            if (win[j].xh > win[j + 1].xh) {
                stu tmp = win[j];
                win[j] = win[j + 1];
                win[j + 1] = tmp;
                swapped = 1;
            }
        }
        if (swapped == 0) break;
    }
}

void output(int n, stu win[]) {
    time_t t = time(NULL);
    struct tm tm = *localtime(&t);
    char filename[64];
    snprintf(filename, sizeof(filename), "%04d%02d%02d.txt", tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);

    FILE *out = fopen(filename, "w");
    if (!out) printf("error...");

    for (int i = 0; i < n; i++) {
        fprintf(out, "%lld %s %s\n", win[i].xh, win[i].name, win[i].class);
    }

    fclose(out);
}

int main()
{
    stu list[100];
    int n = read(list);

    //for(int i=0; i<n; i++) printf("%lld %s %s\n", list[i].xh, list[i].name, list[i].class);

    int r = 114514;
    stu win[100];
    for(int i=0; i<5; i++) {
        srand(((unsigned)time(NULL) + r) % (i+1145)*1419);
        r = rand();
        int realr = r % n;
        win[i] = list[realr];
    }

    bubblesort(win);

    for(int i=0; i<5; i++) {
        printf("%lld %s %s\n", win[i].xh, win[i].name, win[i].class);
    }

    output(5, win);

    
    return 0;
}

运行结果