实验七

#include<stdio.h>
#include<stdlib.h>
#define N 10

typedef struct student
{
    int num;
    char name[20];
    int score;
} STU;

void sort(STU *pst, int n);

int main()
{
    FILE *fin, *fout;
    STU st[N];
    int i;
    
    fin = fopen("file1.dat","r");//read only
    if( !fin ) //the solution to fail
    {
        printf("fail to open file1.dat\n");
        exit (0);
    }
    
    for(i=0; i<N; i++)
        fscanf(fin, "%d %s %d",&st[i].num, st[i].name,&st[i].score);
        
    fclose(fin);
    
    sort(st, N);
    
    fout = fopen("file3.dat","w");
    if(!fout)
    {
        printf("fail to open file1.dat\n");
        exit(0);
    }
    
    for(i=0; i<N; i++)
    {
        printf("%-6d%-10s%3d\n",st[i].num,st[i].name,st[i].score);
        fprintf(fout, "%-6d%-10s%3d\n",st[i].num,st[i].name,st[i].score);        
    }
    fclose(fout);
    
    return 0;
}

void sort(STU *pst,int n)
{
    STU *pi, *pj, t;
    
    for(pi = pst; pi <pst+n-1; pi++)
        for(pj = pi+1; pj < pst+n; pj++)
            if(pi->score < pj->score)
            {
                t = *pi;
                *pi = *pj;
                *pj = t;
            }
}
/*屏幕正确输出，文件file3.dat成功生成
打开后，文件清晰可读*/ 

#include <stdio.h>
#include <stdlib.h>
#define N 10
typedef struct student
{
    int num;
    char name[20];
    int score;
}STU;

void sort(STU *pst, int n);
int main()
{
    FILE *fin, *fout;
    STU st[N];
    int i;
    
    fin = fopen("file1.dat", "r");
    if( !fin )
    {
        printf("fail to open file1.dat\n");
        exit(0);
    }

    for(i=0; i<N; i++)
        fscanf(fin, "%d %s %d", &st[i].num, st[i].name, &st[i].score);
    fclose(fin);
    
    sort(st, N);
    fout = fopen("file4.dat", "wb");
    if( !fout )
    {
        printf("fail to open file1.dat\n");
        exit(0);
    }
    for(i=0; i<N; i++)
        printf("%-6d%-10s%3d\n", st[i].num, st[i].name, st[i].score);

    fwrite(st, sizeof(STU), N, fout);
    fclose(fout);
    
    return 0;
}
void sort(STU *pst, int n)
{
    STU *pi, *pj, t;
    for(pi = pst; pi < pst+n-1; pi++)
        for(pj = pi+1; pj < pst+n; pj++)    
            if(pi->score < pj->score)
            {
                t = *pi;
                *pi = *pj;
                *pj = t;
            }
}
/*信息正确，文件成功生成，信息不能清晰可读（二进制）*/ 

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

#define N 10

typedef struct student
{
    int num;
    char name[20];
    int score;
}STU;

int main()
{
    FILE *fp;
    int i;
    STU s[N];
    
    for(i=0; i<N; i++)
        fscanf(fp,"%d %s %d",&s[i].num,s[i].name,&s[i].score);

    fp = fopen("file4.dat","rb");
    
    fread(&s,sizeof(STU),N,fp);
    
    for(i=0; i<N; i++)
        printf("%-6d%-10s%3d\n",s[i].num,s[i].name,s[i].score);
    
    fclose(fp);
    return 0;
}

#include <stdio.h>
#include <string.h>
const int N = 10;
typedef struct student
{
    long int id;
    char name[20];
    float ob;
    float sub;
    float sum;
    char level[10];
}STU;
void input(STU s[], int n);
void output(STU s[], int n);
void process(STU s[], int n);
int main()
{
    STU stu[N];
    printf("录入%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: 准考证号，姓名，客观题得分，操作题得分，总分，等级 \n");
    output(stu, N);
    
    return 0;
}
void input(STU s[], int n)
{
    FILE *fp;
    int i;
    
    fp=fopen("examinee.txt","r");
    for(i=0; i<N; i++)
        fscanf(fp,"%ld %s %f %f",&s[i].id,s[i].name,&s[i].ob,&s[i].sub);
}

void output(STU s[], int n)
{
    int i,a[N];
    FILE *fp;
    
    for (i = 0; i < n; i++)
        printf("\n%ld %10s %6.2f %6.2f %6.2f %10s\n",s[i].id, s[i].name, s[i].ob, s[i].sub, s[i].sum, s[i].level);
    
        fp = fopen("result.txt", "w+");
        for (i = 0; i < n; i++)
            fprintf(fp,"\n%ld %10s %6.2f %6.2f %6.2f %10s\n",s[i].id, s[i].name, s[i].ob, s[i].sub, s[i].sum, s[i].level);
}

void process(STU s[], int n)
{
        int i,j,k;
    STU temp;
    for(i=0; i<N; i++)
        s[i].sum = 0.4*s[i].ob + 0.6*s[i].sub;
        
        for(i=0;i<n-1;i++)
        for(j=0;j<n-1-i;j++)
        if(s[j].sum<s[j+1].sum)
    {
            temp = s[j];
            s[j] = s[j+1];
            s[j+1] = temp;
        }
    
    for(i=0;i<n;i++)
    {
        if(i<1)
              strcpy(s[i].level,"Excellent");
        else if(i<5&&i>0) 
              strcpy(s[i].level,"Pass");
        else 
              strcpy(s[i].level,"Failed");
    } 
}
/*说实话这章理解特别有问题，所以看了别人的代码才勉强写出来，我尽力去理解*/