student_managerment_system.cpp

平时完成作业做的几个小程序。有数值计算方面的梯形公式求积、simpson算法求积、Jacobi算法求解线性方程组、Gauss-Seidel法求解线性方程组

#include "stdio.h"
#include "math.h"
#include "string.h"
#include "stdlib.h"
#include "malloc.h"
#include "time.h"

#define TRUE  1
#define FALSE 0
#define OK    1
#define ERROR 0
#define NULL  0

#define MAX 100  //设置信息库最大的容量。可根据情况修改。



FILE * fp;
char ch;
int NUM;    //用全局变量NUM记录以填入的记录的数目

struct student_type  //结构体定义学生信息存储体
{
	int num;
	char name[10];
	float score;
}student[MAX],temp;

int from_keyboard()   //从键盘输入信息的子函数
{
	int i=0;
//	printf("standard format :(number-name-score)one line per student.Please do follow the standerd format\n");
	while(student[i].num!=0)
		i++;   //找到当前第一个空记录的位置
new_record: printf("please input the number of this student:\n");
	scanf("%d",&student[i].num);
	printf("please input the name of this student:\n");
	scanf("%s",&student[i].name);
	printf("please input the score of this student:\n");
	scanf("%f",&student[i].score);
	printf("A new record has been successfully put in.\npress 'c' to put in another record,'s' to stop and return to menu\n");
retry:	ch=getchar();
	if (ch=='c') 
	{
		i++;
		goto new_record;
	}
	else if(ch=='s')
		return TRUE;
	else goto retry;
	printf("------------------------------------------------------\n");	
}

int from_file()  // 从文件读入信息的子函数
{
	int i=0,j=0;
	char FILENAME[30];
try_again:	printf("please input the name of the source file(with path)\n");
	scanf("%s",FILENAME);
	if((fp=fopen("FILENAME","r"))==NULL)
	{
		printf("cann't open the file.please check your input \n");
		printf("press 'c' to try again or 's' to get back to the menu\n");
retry_2:ch=getchar();
        if(ch=='s')
			return FALSE;
		else if(ch=='c')
			goto try_again;
		else goto retry_2;
	}
	while(ch=getc(fp)!=EOF)
	{		
        student[i].num=getw(fp);
		fgets(student[i].name,10,fp);
		fscanf(fp,"%f",&student[i].score);
	}
	return TRUE;
	printf("------------------------------------------------------\n");	
}

void num_man_and_boy_sort()  //按学号由大到小排序子函数
{
	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;	
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(student[i].num<student[j].num)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");		
}



void name_man_and_boy_sort()  //按名字由大到小排序子函数
{
	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;	
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(strcmp(student[i].name,student[j].name)<0)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");
}

void score_man_and_boy_sort() //按加权平均成绩由大到小排序子函数
{

	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(student[i].score<student[j].score)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");
}

void num_retrorse_sort()   //按学号由小到大反序排序子函数
{

	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(student[i].num>student[j].num)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");
}

void name_retrorse_sort()  //按名字由小到大反序排序子函数
{
	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;	
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(strcmp(student[i].name,student[j].name)>0)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");
}

void score_retrorse_sort()  //按加权平均成绩由小到大反序排序子函数
{
	int i=0,j=0;
	struct student_type temp;
	while(student[i].num!=0)
	     i++;   //找到当前第一个空记录的位置
	NUM=i;	
    for(i=0;i<NUM;i++)
		for(j=i;j<NUM;j++)
		{
			if(student[i].score>student[j].score)
			{
				temp.num=student[i].num;
				strcpy(temp.name,student[i].name);
				temp.score=student[i].score;

				student[i].num=student[j].num;
				strcpy(student[i].name,student[j].name);
				student[i].score=student[j].score;

				student[j].num=temp.num;
				strcpy(student[j].name,temp.name);
				student[j].score=temp.score;
			}
		}
		printf("排序完毕。下面是经过排序后的数据：\n学号\t姓名\t加权平均成绩\n");
		for(i=0;i<NUM;i++)
			printf("%d\t%s\t%f\n",&student[i].num,student[i].name,student[i].score);
		printf("------------------------------------------------------\n");
}


void main_menu()  //主菜单
{
	printf("\t学生成绩管理信息系统\n");
	printf("Please key_in the corresponding number(1-9) to start work:\n");
	printf("1.学生信息输入\n2.按学号排序\n3.按姓名排序\n4.按加权平均成绩排序\n5.按学号查询\n6.按姓名查询\n7.按加权平均成绩查询\n8.保存学生信息\n9.退出本系统\n");
	printf("------------------------------------------------------\n");
}

void input()  //1.学生信息输入
{
	int sub_menu;
	printf("select the source of the datas\n");
label_1:    printf("1.从键盘输入\n2.从文本文件读入\n3.返回主菜单\n");
    scanf("%d",&sub_menu);
	switch (sub_menu)
	{
	case 1: from_keyboard();break;
	case 2: from_file();break;
	case 3: return;break;
	default:printf("illegal input!please re_enter the number\n");goto label_1;
	}
	printf("------------------------------------------------------\n");
}

void number_sort()  //2.按学号排序
{	
	int sub_menu;
	printf("select the source of the datas\n");
label_2:	printf("1.从小到大排序\n2.从大到小排序\n3.返回子菜单\n");
    scanf("%d",&sub_menu);
	switch (sub_menu)
	{
	case 1: num_man_and_boy_sort();break;
	case 2: num_retrorse_sort();break;
	case 3: return;break;
	default:printf("illegal input!please re_enter the number\n");goto label_2;
	}
	printf("------------------------------------------------------\n");
}

void name_sort()  //3.按姓名排序
{
	int sub_menu;
	printf("select the source of the datas\n");
label_3:	printf("1.从小到大排序\n2.从大到小排序\n3.返回子菜单\n");
    scanf("%d",&sub_menu);
	switch (sub_menu)
	{
	case 1:name_man_and_boy_sort();break;
	case 2:name_retrorse_sort();break;
	case 3:return;break;
	default:printf("illegal input!please re_enter the number\n");goto label_3;
	}
	printf("------------------------------------------------------\n");
}

void score_sort()  //4.按加权平均成绩排序
{
	int sub_menu;
	printf("select the source of the datas\n");
label_4:	printf("1.从小到大排序\n2.从大到小排序\n3.返回子菜单\n");
    scanf("%d",&sub_menu);
	switch (sub_menu)
	{
	case 1:score_man_and_boy_sort();break;
	case 2:score_retrorse_sort();break;
	case 3:return;break;
	default:printf("illegal input!please re_enter the number\n");goto label_4;
	}
	printf("------------------------------------------------------\n");
}

int number_inquire()  //5.按学号查询
{
	int i=0,j=0,k;
	int m;
	while(student[i].num!=0)
		i++;	
	num_man_and_boy_sort();  //查询前先排序
    printf("please input the number of the student you want to inquire:\n");
	scanf("%d",&m);
	while(i>j)
	{
		k=(i+j)/2;
		if(m==student[k].num)
		{
			printf("data found successfully.list as bellow:\n学号\t姓名\t加权平均成绩\n");
			printf("%d\t%s\t%f\n",&student[k].num,student[k].name,student[k].score);
			return TRUE;
		}
		else if(m<student[k].num)
			j=k+1;
		else
			i=k-1;
	}
	printf("item not found.please check your input and try again\n");
	return FALSE;
	printf("------------------------------------------------------\n");
}

int name_inquire()   //6.按姓名查询
{
	int i=0,j=0,k;
	char N[10];
	while(student[i].num!=0)
		i++;	
	name_man_and_boy_sort();  //查询前先排序
    printf("please input the name of the student you want to inquire:\n");
	scanf("%S",N);
	while(i>j)
	{
		k=(i+j)/2;
		if(strcmp(N,student[k].name)==0)
		{
			printf("data found successfully.list as bellow:\n学号\t姓名\t加权平均成绩\n");
			printf("%d\t%s\t%f\n",&student[k].num,student[k].name,student[k].score);
			return TRUE;
		}
		else if(strcmp(N,student[k].name)<0)
			j=k+1;
		else
            i=k-1;	
	}
	printf("item not found.please check your input and try again\n");
	return FALSE;
	printf("------------------------------------------------------\n");
}

int score_inquire()    //7.按加权平均成绩查询
{
	int i=0,j=0,k;
	int m;
	while(student[i].num!=0)
		i++;	
	score_man_and_boy_sort();  //查询前先排序
    printf("please input the score of the student you want to inquire:\n");
	scanf("%f",&m);
	while(i>j)
	{
		k=(i+j)/2;
		if(m==student[k].score)
		{
			printf("data found successfully.list as bellow:\n学号\t姓名\t加权平均成绩\n");
			printf("%d\t%s\t%f\n",&student[k].num,student[k].name,student[k].score);
			return TRUE;
		}
		else if(m<student[k].score)
			j=k+1;
		else
			i=k-1;
	}
	printf("item not found.please check your input and try again\n");
	return FALSE;
	printf("------------------------------------------------------\n");
}


void save()         //8.保存学生信息 
{
	int i=0,j=0;
	printf("To save this file,please input a new name for this file\n");
    char FILENAME[20];
	scanf("%s",FILENAME);
	fp=fopen("FILENAME","w+");	
	while(student[i].num!=0)
		i++;
	for(j=0;j<i;j++)
	{
	    putw(student[j].num,fp);
	    fputs(student[j].name,fp);
     	fprintf(fp,"%f",student[j].score);
	}
	fclose(fp);
	printf("------------------------------------------------------\n");
}



void main(void)    
{
	int menu,i;
    for(i=0;i<MAX;i++)
		student[i].num=0;  //初始化，将学号全初始化为0，以作为标志位区分是否已填入数据
label:	main_menu();
	scanf("%d",&menu);
	switch(menu)
	{
	case 1: input();break;
	case 2: number_sort();break;
	case 3: name_sort();break;
    case 4: score_sort();break;
	case 5: number_inquire();break;
	case 6: name_inquire();break;
    case 7: score_inquire();break;
	case 8: save();break;
	case 9: exit(1);break;
	default:printf("illegal input!please re_enter the number\n");goto label;
	}
	printf("------------------------------------------------------\n");
	goto label;
	
}