Thread: Need help about delete and add in struct

Hi, I'm new to C program, so the task is to add maximum of 4 employees data, then remove one, to show 3 of them. then add a new one, and to show all 4 of them. I need help to find out what's wrong wit this code

code:

Code:

#define _CRT_SECURE_NO_WARNINGS






#include <stdio.h>






// Define Number of Employees "SIZE" to be 2










// Declare Struct Employee 
#define SIZE 4


struct employee {
    int age, id;
    double salary;
};








/* main program */


int main(void) {


    struct employee emp[4] = { 0 };


    int option = 0;
    int true = 0;
    int i = 0;
    int n1 = 0;
    int n2 = 0;
    int n3 = 0;


    int true2 = 0;
    // Declare a struct Employee array "emp" with SIZE elements 


    // and initialize all elements to zero










    printf("---=== EMPLOYEE DATA ===---\n\n");






    do {


        // Print the option list


        printf("1. Display Employee Information\n");


        printf("2. Add Employee\n");


        printf("3. Update Employee Salary\n");


        printf("4. Remove Employee\n");


        printf("0. Exit\n\n");


        printf("Please select from the above options: ");






        // Capture input to option variable


        scanf("%d", &option);


        printf("\n");






        switch (option) {


        case 0:    // Exit the program


            printf("Exiting Employee Data Program. Good Bye!!!");
            printf("\n");




            break;


        case 1: // Display Employee Data


                // @IN-LAB






            printf("EMP ID  EMP AGE EMP SALARY\n");


            printf("======  ======= ==========\n");


            for (i = 0; i < 4; i++)
            {
                if (emp[i].id != 0) {




                    printf("%6d%9d%11.2lf\n", emp[i].id, emp[i].age, emp[i].salary);
                }
            }


            printf("\n");












            // Use "%6d%9d%11.2lf" formatting in a   


            // printf statement to display


            // employee id, age and salary of 


            // all  employees using a loop construct 






            // The loop construct will be run for SIZE times 


            // and will only display Employee data 


            // where the EmployeeID is > 0






            break;


        case 2:    // Adding Employee


                // @IN-LAB






            printf("Adding Employee\n");


            printf("===============\n");


            if (n1 < 4) {
                for (i = 0; i < 4; i++)
                {
                    if (emp[i].id == 0)
                    {




                        printf("Enter Employee ID: ");
                        scanf("%d", &emp[n1].id);
                        printf("Enter Employee Age: ");
                        scanf("%d", &emp[n1].age);
                        printf("Enter Employee Salary: ");
                        scanf("%lf", &emp[n1].salary);


                        printf("%d\n", n1);
                        i += SIZE;
                    }
                }
                n1++;
            }
            else {
                printf("ERROR!!! Maximum Number of Employees Reached\n");
                printf("\n");
            }




            // Check for limits on the array and add employee 


            // data accordingly. 
            break;




        case 3:


            printf("Update Employee Salary\n");


            printf("===============\n");




            do {
                printf("Enter Employee ID: ");
                scanf("%d", &n2);


                for (i = 0; i < n1; i++)
                {


                    if (n2 == emp[i].id)
                    {
                        true = 1;
                        printf("The current salary is %.2f\n", emp[i].salary);
                        printf("\nInput new salary: ");
                        scanf("%lf", &emp[i].salary);
                    }






                }
                if (true == 0)
                {
                    printf("wrong number \n");
                }


            } while (true == 0);
            break;




        case 4:


            printf("Remove Employee\n");


            printf("===============\n");
            true2 = 0;
            do {
                printf("Enter Employee ID: ");
                scanf("%d", &n3);


                for (i = 0; i < 4; i++) {
                    if (n3 == emp[i].id)
                    {
                        true2 = 1;
                        printf("Employee %d will be removed", emp[i].id);
                        emp[i].id = 0;
                        n1--;
                    }
                }




                if (true2 == 0) {
                    printf("wrong number \n");
                }
            } while (true2 == 0);












            break;








        }


        if (option > 4)
        {
            printf("ERROR: Incorrect Option: Try Again\n");
            printf("\n");
        }


    } while (option != 0);














    return 0;


}

So it can remove the employee, but once I add the new one, it will only show 3 of the employee data instead of all 4 of them.


Sorry I'm really new to this, and this code I wrote is already with someones help. So please bare with me.