Question

please use the c language

Assignment 12 The program to write in this assignment is a program that calculates score statistics and manages the grades of the students. First, the student list and are given in a file named "student.dat" as in the following: 이성우 77 홍길동 88 scores 201 1710086 2012700091 This program reads the input file "student.dat" and keeps this data in a linear linked list. Each node must be a struct which contains the following: student id student_name, score, grade The grades are decided by each students' scores if 80 score < 90, grade B C if 60 s score < 70, grade = D if 90 s score, grade A if 70 s score < 80, grade if score < 60, grade = = Basis and Practice in Programm ing Assignment 12 This program must indude the following functions: 1) Calculate mean and standard deviation Given student scores x i= 1, n(= no. of students), it must calculate the S and Standa rd Deviation, Mean, 8= 2) Searching stud ent information: Search within the linear linked list with the student_id or student name, and print the following student_id 2012700091 If there is no such student in the record, then the program prints "no such student! student name 홍길동 grade Score 88 3) Change student score Search through the linear linked list with the student_id change the score of that student. The grade must be changed according to the new score. If there is no such student in the record, then the program prints "no such student!" student name, and or Basis and Practice in Programming

Answer 1

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

typedef struct Student{
char student_id[11];
char student_name[20];
int score;
char grade;
} Student;

typedef struct Node{
Student s;
struct Node *next;
} Node;

//Function to add to linked list
Node add(Node list, Student s){
Node *newNode = (Node*)malloc(sizeof(Node));
newNode->s = s;
newNode->next = NULL;

if(list == NULL)
list = newNode;
else {
Node *ptr = list;
while (ptr->next != NULL)
ptr = ptr->next;
ptr->next = newNode;
}
return list;
}

//Function to return grade based on score
char getGrade(int score){
if(score >= 90)
return 'A';
else if(score >= 80)
return 'B';
else if(score >= 70)
return 'C';
else if(score >= 60)
return 'D';
else
return 'F';
}

//Function to read data from file into linked list
Node readFromFile(Node list){
FILE *f = fopen("student.dat", "r");//Open file in read mode
if(f == NULL){
printf("Error: Unable to open file\n");
exit(EXIT_FAILURE);
}
Student s;
while(!feof(f)){
fscanf(f, "%s %s %d", s.student_id, s.student_name, &s.score);//Read a record
s.grade = getGrade(s.score);//Get grade based upon score
list = add(list, s);
}
fclose(f);//Close file
return list;
}

//Function to return mean of student scores
double getMean(Node *list){
Node *ptr = list;
int n = 0;
double mean = 0.0;
while(ptr != NULL){
mean += ptr->s.score;
n++;
ptr = ptr->next;
}
mean = mean/n;
return mean;
}

//Function to return standard deviation of student scores
double getStandardDeviation(Node *list){
Node *ptr = list;
double mean = getMean(list);
double sd = 0;
int n = 0;
while(ptr != NULL){
sd += pow(ptr->s.score - mean, 2);
n++;
ptr = ptr->next;
}
sd = sqrt(sd/(n - 1));
return sd;
}

//Function to search linked list for student with student id
void searchWithStudentID(Node list, char student_id){
Node *ptr = list;
while(ptr != NULL){
if(strcmp(ptr->s.student_id, student_id) == 0){
printf("student_id\tstudent_name\tscore\tgrade\n");
printf("%s\t%s\t\t%d\t%c\n", ptr->s.student_id, ptr->s.student_name, ptr->s.score, ptr->s.grade);
return;
}
ptr = ptr->next;
}
printf("No such student!\n");
}

//Function to change student score by searching linked list using student id
void changeScore(Node list, char student_id){
Node *ptr = list;
int score;
while(ptr != NULL){
if(strcmp(ptr->s.student_id, student_id) == 0){
printf("Enter new score: ");
scanf("%d", &score);
ptr->s.score = score;
ptr->s.grade = getGrade(score);
return;
}
ptr = ptr->next;
}
printf("No such student!\n");
}

int main(){
Node *list = NULL;//Create an empty list

list = readFromFile(list);

printf("Mean of student scores: %f\n", getMean(list));
printf("Standard deviation of student scores: %f\n", getStandardDeviation(list));

printf("\nSearching for student with id 2011710088:\n");
searchWithStudentID(list, "2011710088");

printf("\nSearching for student with id 2011710095:\n");
searchWithStudentID(list, "2011710095");

printf("\nChanging score of student with id 2011710088:\n");
changeScore(list, "2011710088");

printf("\nChanging score of student with id 2011710095:\n");
changeScore(list, "2011710095");

return 0;
}

Sample student.dat file:

| student.dat Notepad File Edit Format View Help 2011710086 Jack 77 2011710087 Abel 88 2011710088 Cain 83 2011710089 Eve 96 2011710090 Adam 72 2011710091 Josh 79

Sample terminal output:

CAUsers\Shubham\Desktop\readSquare.exe Mean of student scores: 82.500000 Standard deviation of student scores: 8.549854 Searching for student with id 2011710088: student_name Cain student_id 2011710088 grade score 83 B Searching for student with id 2011710095: No such student! Changing score of student with id 2011710088: Enter new score: 98 Searching for student with id 2011710088: student id 2011710088 student_name Cain grade score 98 A Changing score of student with id 2012700091: No such student! Process exited after 3.682 seconds with return value 0 Press any key to continue