problem with code

[MPrestonf12]

I can not get this code to work i've tried everything!!

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>

int main(void)
{
char mystr;
char *p;
char retval;

printf("%s\n", "enter letter");

scanf("%s", mystr);

p = &mystr;

retval = *p;

printf(retval);

system("pause");
return 0;
}