Employee Info through Linked List and finding average sal

#include<stdio.h>
#include<malloc.h>
#include<string.h>
struct emp
{

        char name[10];
        char designation[10];
        float salary;
        struct emp *ptr;
};

struct emp * addelement(struct emp *,char name[],char des[],float );
void display(struct emp *);
void average(struct emp *);

int main()
{

        int num,i;
        struct emp *head;
        float sal;
        head=NULL;
        char name[10],des[10];
        printf("\n Enter the number of employees to be added to the database :");
        scanf("%d",&num);
        for(i=1;i<=num;i++)
        {
                printf("Enter the name of the employee :");
                scanf("%s",name);
                printf("\n Enter the designation of the employee :");
                scanf("%s",des);
                printf("\n Enter the salary of the employee : ");
                scanf("%f",&sal);
                head=addelement(head,name,des,sal);
        }

        printf("\n The employee information is as follows ");
        display(head);

        average(head);
}

struct emp * addelement(struct emp *head,char name[10],char des[10],float sal)

        {
                struct emp  *newnode;

                newnode=(struct emp *)malloc(sizeof(struct emp));

                strcpy(newnode->name,name);
                strcpy(newnode->designation,des);
                newnode->salary=sal;
		if(head==NULL)

                {

                        newnode->ptr=NULL;

                        return newnode;

                }
                else

                {

                        newnode->ptr=head;

                        return newnode;
                }

        }

void display(struct emp *p3)

        {

                    if(p3==NULL)

                {



                        printf("\n The list is empty \n");

                }



                while(p3!=NULL)

                {

                        printf("\n Employee Name: %s,Employee Designation: %s,salary: %f",p3->name,p3->designation,p3->salary);

                        p3=p3->ptr;

                }

        }

void average(struct emp *p4)

{
        float average,sal=0;
        int n=0;
        if(p4==NULL)
        {

                printf("\n The List is empty");

        }

        while(p4!=NULL)
        {
                if((strcmp(p4->designation,"manager")==0)||(strcmp(p4->designation,"MANAGER")==0))
                {
                        sal=sal+(p4->salary);
                        n++;
                }
                p4=p4->ptr;
        }
                average=(sal)/n;
                printf("\n The Average salary of manager in the organisation : %f",average);
}