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#include #include using namespace std; //structure to store details struct Student { int rollnumber; string name; string phone; float percentage; struct Student *next; }* head; //function to add details void insert(int rollnumber, string name, string phone, float percentage) { //creating a struct instance, new is used to allocate memory struct Student * student = new Student; //assigning varibles student->rollnumber = rollnumber; student->name=name; student->phone= phone; student->percentage = percentage; student->next = NULL; if(head==NULL){ // if head is NULL // set student as the new head head = student; } else{ // if list is not empty // insert student in beginning of head student->next = head; head = student; } } //function to serach details of a student void search(int rollnumber) { //using temp structure variable struct Student * temp = head; //searching for roolno details while(temp!=NULL) { //rollnumber found condition if(temp->rollnumber==rollnumber) { //here cout is used to print details cout<<"Roll Number: "<rollnumber<name<phone<percentage<next; } //details not found condition cout<<"Student with roll number "<rollnumber==rollnumber) { //cin is used to get input and cout is to print output cout<<"Record with roll number "<>temp->name; cout<<"Enter new phone number: "; cin>>temp->phone; cout<<"Enter new percentage: "; cin>>temp->percentage; cout<<"Updation Successful!!!"<next; } //roolnumber not found condition cout<<"Student with roll number "<rollnumber==rollnumber){ cout<<"Record with roll number "<next; delete temp1; } else{ // temp1 is the node we need to delete // temp2 is the node previous to temp1 temp2->next = temp1->next; delete temp1; } cout<<"Record Successfully Deleted !!! "; return; } temp2 = temp1; temp1 = temp1->next; } //not found case cout<<"Student with roll number "<rollnumber<name<phone<percentage<next; } } //main function int main() { head = NULL; int choice; //decalring variables as string type string name; string phone; int rollnumber; float percentage; //ptinitng output cout<<"1 to insert student details 2 to search for student details 3 to delete student details 4 to update student details 5 to display all student details"; //getting inut from user cout<<" Enter Choice: "; cin>>choice; switch (choice) { //case 1 is to add details case 1: cout<<"Enter roll number: "; cin>>rollnumber; cout<<"Enter name: "; cin>>name; cout<<"Enter phone number: "; cin>>phone; cout<<"Enter percentage: "; cin>>percentage; insert(rollnumber, name, phone, percentage); break; //when choice ==2 then this case case 2: cout<<"Enter roll number to search: "; cin>>rollnumber; search(rollnumber); break; //if choice == 3 case 3: cout<<"Enter roll number to delete: "; cin>>rollnumber; Delete(rollnumber); break; //if choice ==4 case 4: cout<<"Enter roll number to update: "; cin>>rollnumber; update(rollnumber); break; //if choice==5 case 5: display(); break; //wrong case default : cout<<"Wrong Choice"; } }