C language small project - student achievement management system

System interface and related requirements

1） System operation , Open the following interface . List the system help menu （ Command menu ）, Prompt for commands .

2） You haven't entered your grades at the beginning , So enter the command L And I can't list my grades . Should prompt “ The grade sheet is empty ！ Please use the command first T Enter student scores .”
Empathy , When inputting other grade processing commands, it will also be processed accordingly .

3） Enter the command T, call Type Sub function entry score .
The interface prompts you to enter the number of students

Input 3 prompt 3 Students 3 Course results , List the header of the transcript “ Student number Chinese language and literature mathematics English ”, Prompt student number ：1

Input 1 Student No 3 Course results , Use space between , End of carriage return . Prompt student number ：2

Input 2 Student No 3 Course results , Use space between , End of carriage return . Prompt student number ：3

Input 3 Student No 3 Course results , Use space between , End of carriage return .Type End of subfunction call , return . Prompt for commands .

4） Enter the command L , call List Sub function output score table .List End of subfunction call , return . Prompt for commands .

5） Enter the command A , call Average The subfunction calculates the average score , Tips “ The average score has been calculated . Please use the command L see .” Average End of subfunction call , return . Prompt for commands .
Enter the command L , call List Sub function output score table .List End of subfunction call , return . Prompt for commands .

6） Enter the command P , call Sort The sub function sorts the student records from high to low according to the average score , Tips “ To complete the order . Please use the command L see .” Sort End of subfunction call , return . Prompt for commands .

Enter the command L , call List Sub function output score table .List End of subfunction call , return . Prompt for commands .

7） Enter the command S , call Search Sub function queries student grades , Tips “ Enter the student number to query ”.

Input 2 find 2 Student No. and output .Search End of subfunction call , return . Prompt for commands .

8） Enter the command C Execute the clear screen function statement system(“clear”);

Clear everything on the screen . Prompt for commands .

9） Enter the command H call Help The sub function displays the help menu .Help End of subfunction call , return . Prompt for commands .

10） Enter the command Q , Exit the system .

Be careful ：
1） When outputting array elements , The student number should be handled separately , The output is an integer （ Namely reservation 0 Decimal place ）. Empathy , When calculating grades, you should also put the number 1 Put aside the student number in the column , Only the second 2 After column . Achievement retention 1 Decimal place .
2） Number of students n Throughout , adopt n The value of determines whether the sub function of the current command can be called and executed . for example ： When n=0 when , Note that the score has not been entered . And once you enter a command T, That is to call Type The sub function has entered the score , be n The value of is no longer 0. When n！=0 when , You can perform other performance operations , But you can no longer perform the operation of employment results . So when the command entered by the user cannot be executed , Prompt should be given .

Code

#include <stdio.h>
#include <stdlib.h>
//#include "hs.h"
struct student
{
    
	int id;
	float yw;
	float sx;
	float wy;
	float pj;
};
void help(void);
int type(struct student *p);
void list(struct student *p,int n);
void average(struct student *p,int n);
void search (struct student *p);
void sort(struct student *p,int n);
int main(int argc, const char *argv[])
{
    
	char ch;
	struct student stu[32];
	int n=0;
	while(1)
	{
    
		printf(" Please enter a command  = ");
		//getchar();
		scanf("%c",&ch);
		putchar(10);
		if(ch=='T')
		{
    
			n=type(stu);
		}
		else if(ch=='L')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
				list(stu,n);
		}
		else if(ch=='A')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				average(stu,n);
				printf(" The average score has been calculated , Please use the command L see ！\n");
				putchar(10);
			}
		}
		else if(ch=='H')
			help();
		else if(ch=='C')
			system("clear");
		else if(ch=='S')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				search(stu);
				putchar(10);
			}
		}
		else if(ch=='P')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				sort(stu,n);
				putchar(10);
			}
		}
		else if(ch=='Q')
		{
    
			printf("Press any key to continue!\n");
			return -1;
		}
		getchar();
	}
	return 0;
}
int type(struct student *p)
{
    
	int n=0;
	printf(" Please input the number of students ：");
	scanf("%d",&n);
	printf(" Please enter the student's grades in three courses ：\n");
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages \n");
	for(int i=0;i<n;i++)
	{
    
		printf("%d ",i+1);
		struct student stu[i];
		scanf("%f %f %f",&(p+i)->yw,&(p+i)->sx,&(p+i)->wy);
	}
	return n;
}
void list(struct student *p,int n)
{
    
	printf(" The students' grades are as follows ：\n");
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages   average \n");
	for(int i=0;i<n;i++)
	{
    
		printf("%d ",i+1);
		printf("%.1f %.1f %.1f %.1f",p->yw,p->sx,p->wy,p->pj);
		p++;
		putchar(10);
	}
}
void average(struct student *p,int n)
{
    
	for(int i=0;i<n;i++)
	{
    
		(p->pj)=((p->yw)+(p->sx)+(p->wy))/3;
		p++;
	}
}
void help(void)
{
    
	printf("**********************************\n");
	printf(" *  Student achievement management system —— In the help menu  * \n");
	printf("**********************************\n");
	printf(" * H =  Show help menu  * \n");
	printf(" * T =  Score entry  * \n");
	printf(" * A =  Calculate the student average  * \n");
	printf(" * L =  List the transcript  * \n");
	printf(" * P =  Sort by GPA from high to low  * \n");
	printf(" * S =  Inquire the student's grade by student number  * \n");
	printf(" * C =  Clear the screen  * \n");
	printf(" * Q = Exit the system  * \n");
	printf("**********************************\n");
	printf(" *Copyright(c) 2022.3.15 By liq* \n");
	printf("**********************************\n");
}
void search(struct student *p)
{
    
	int s=0;
	printf(" Please enter the student number to be queried ：");
	scanf("%d",&s);
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages   average \n");
	printf("%d %.1f %.1f %.1f %.1f",s,(p+s-1)->yw,(p+s-1)->sx,(p+s-1)->wy,(p+s-1)->pj);
	putchar(10);
}
void sort(struct student *p,int n)
{
    
	struct student temp;
	int i,j;
	for(i=0;i<n;i++)
	{
    
		for(j=0;j<n-i-1;j++)
		{
    
			if(p[j].pj<p[j+1].pj)
			{
    
				temp=p[j];
				p[j]=p[j+1];
				p[j+1]=temp;
			}
		}
	}
	printf(" Sort complete , Please use the command L see ！\n");
}

Be careful

If it needs to be written in separate documents .
Just take out the function part of the above code , Create two new files ：fun.c、fun.h. among fun.c File is used to store the structure declaration and function part of the above code （ Add the corresponding header file ）.fun.h Used to store structure declaration and function declaration （ Add the corresponding header file ）.
Add the corresponding header file to the main function ：#include “fun.h”（ Double quotes , No <>).
When compiling, the main function and the newly created fun.c Compile files together , The operation is the same as before , use ./a.out Can run .
The details are shown in the following figure ：
1. Create two new files （ The same name , Different suffixes ）, Compile and run （ You need to compile multiple files at the same time ）.

2.hs.c Store the structure declaration and the corresponding function （ The functions in this can also be split into other files , I won't split it here ）.

#include <stdio.h>
#include <stdlib.h>
struct student
{
    
	int id;
	float yw;
	float sx;
	float wy;
	float pj;
};
int type(struct student *p)
{
    
	int n=0;
	printf(" Please input the number of students ：");
	scanf("%d",&n);
	putchar(10);
	printf(" Please enter the student's grades in three courses ：\n");
	putchar(10);
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages \n");
	for(int i=0;i<n;i++)
	{
    
		printf("%d ",i+1);
		struct student stu[i];
		scanf("%f %f %f",&(p+i)->yw,&(p+i)->sx,&(p+i)->wy);
	}
	putchar(10);
	return n;
}
void list(struct student *p,int n)
{
    
	printf(" The students' grades are as follows ：\n");
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages   average \n");
	for(int i=0;i<n;i++)
	{
    
		printf("%d ",i+1);
		printf("%.1f %.1f %.1f %.1f",p->yw,p->sx,p->wy,p->pj);
		p++;
		putchar(10);
	}
	putchar(10);
}
void average(struct student *p,int n)
{
    
	for(int i=0;i<n;i++)
	{
    
		(p->pj)=((p->yw)+(p->sx)+(p->wy))/3;
		p++;
	}
}
void help(void)
{
    
	printf("**********************************\n");
	printf(" *  Student achievement management system —— In the help menu  * \n");
	printf("**********************************\n");
	printf(" * H =  Show help menu  * \n");
	printf(" * T =  Score entry  * \n");
	printf(" * A =  Calculate the student average  * \n");
	printf(" * L =  List the transcript  * \n");
	printf(" * P =  Sort by GPA from high to low  * \n");
	printf(" * S =  Inquire the student's grade by student number  * \n");
	printf(" * C =  Clear the screen  * \n");
	printf(" * Q = Exit the system  * \n");
	printf("**********************************\n");
	printf(" *Copyright(c) 2022.3.15 By liq* \n");
	printf("**********************************\n");
}
void search(struct student *p)
{
    
	int s=0;
	printf(" Please enter the student number to be queried ：");
	scanf("%d",&s);
	putchar(10);
	printf(" Student number   Chinese language and literature   mathematics   Foreign Languages   average \n");
	printf("%d %.1f %.1f %.1f %.1f",s,(p+s-1)->yw,(p+s-1)->sx,(p+s-1)->wy,(p+s-1)->pj);
	putchar(10);
}
void sort(struct student *p,int n)
{
    
	struct student temp;
	int i,j;
	for(i=0;i<n;i++)
	{
    
		for(j=0;j<n-i-1;j++)
		{
    
			if(p[j].pj<p[j+1].pj)
			{
    
				temp=p[j];
				p[j]=p[j+1];
				p[j+1]=temp;
			}
		}
	}
	printf(" Sort complete , Please use the command L see ！\n");
}

3.hs.h Storage structure declaration and hs.c The function declaration corresponding to the function inside .

#include <stdio.h>
#include <stdlib.h>
struct student
{
    
	int id;
	float yw;
	float sx;
	float wy;
	float pj;
};
int type(struct student *p);
void list(struct student *p,int n);
void average(struct student *p,int n);
void help(void);
void search(struct student *p);
void sort(struct student *p,int n);

4.main function

#include <stdio.h>
#include <stdlib.h>
#include "hs.h"
int main(int argc, const char *argv[])
{
    
	char ch;
	struct student stu[32];
	int n=0;
	while(1)
	{
    
		printf(" Please enter a command  = ");
		scanf("%c",&ch);
		putchar(10);
		if(ch=='T')
		{
    
			n=type(stu);
		}
		else if(ch=='L')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
				list(stu,n);
		}
		else if(ch=='A')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				average(stu,n);
				printf(" The average score has been calculated , Please use the command L see ！\n");
				putchar(10);
			}
		}
		else if(ch=='H')
			help();
		else if(ch=='C')
			system("clear");
		else if(ch=='S')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				search(stu);
				putchar(10);
			}
		}
		else if(ch=='P')
		{
    
			if(n==0)
			{
    
				printf(" The grade sheet is empty ！ Please use first. T Enter the score ！\n");
				putchar(10);
			}
			else
			{
    
				sort(stu,n);
				putchar(10);
			}
		}
		else if(ch=='Q')
		{
    
			printf("Press any key to continue!\n");
			return -1;
		}
		getchar();
	}
	return 0;
}