How to match a varible in a struct array, then the position - c

Question

first post here. Somewhat new to coding aswell.
Right now I'm at halt. What I need to do is get input from the user of an employee id then find it in a struct array variable, and keep asking until a correct one is entered.. all in a do-while loop. Then I need to print the salary of that employee and update it to something new.
I'm having a hard time trying to figure out how to search the struct array for that employee ID, then when that's done, saving what position the struct array in is so I can print THAT employees salary, then update it to something else.
Heres some code to show the struct array
#define SIZE 4
struct employee{
int id[SIZE] ;
int age[SIZE];
double salary[SIZE];
};
/* main program */
int main(void) {
struct employee emp[SIZE] = { 0 };
Here is some to show the code to what I've done
case 3: //Update Employee
printf("Update Employee Salary\n");
printf("======================\n");
int employid;
do{
printf("Enter Employee ID: ");
scanf("%d", &employid);
}while(employid != emp->id[SIZE]);
printf("The current salary is %lf", emp->salary[SIZE]);
break;
I know this is wrong. The While just looks at the current position, and the printf only prints the salary of the current arrays employee aswell.
Any help would be appreciated.
Bonus:
Notice when I'm assigning/working with my struct, I have to put "->" to actually tell my compiler that I'm pointing to that specific variable in the struct. Usually I put "." and have no idea why I need to put ->.. I just found the fix online.
Usually it would be "emp.id[SIZE];"
NOT "emp->id[SIZE];"
Anyone have any ideas?
Thanks all

Answer 1

Considering that your input to the structure is right, there are few things you can do.
The thing is you need to realize that you need a while/for loop to iterate over the employee array.
Second thing is, here you are not comparing it correctly. You are just comparing with the first element.
Now what you can do is
bool found = false;
int foundEmpId = -1;
do{
printf("Enter Employee ID: ");
scanf("%d", &employid);
for(size_t i = 0; i< SIZE; i++)
if( emp[i].id == employid ){
foundEmpId = employid;
found = true;
break;
}
}while(!found);
// do your work.
Now this is simply the O(n) searching.
Apart from that there is one thing you can see in my code. I am using emp[i].id. Here the structure I considered is
struct employee{
int id ;
int age;
double salary;
};
If you think of an employee these are the attributes you need to add over here. What you did was working with different groups of employees.
Here you will work like this
struct employee emps[SIZE];
...
...
// the attributes of employee will be inputted like this
// if( scanf("%d",&emps[i].id) == 1 ) { /* */ }
...
Why did you need emp->id[SIZE] here?
Dissecting the emp->id[SIZE] is equivalent to (*emp).id[SIZE] or more precisly emp[0].id[SIZE].
To summarize the problems/suggestion:-
P The portion of the code that you have shown it shows that you are not comparing with all the employees.
P You have created groups of employees. But you are not iterating or using all the groups. You just worked on first employee group.
S Instead of using the array of employee groups you should simply use array of employees. Or Even if you do use groups of enployess then just one group will suffice.