C PROGRAMMING-- SIZE OF

#include<stdio.h>
#include<conio.h>
void main()
{ clrscr();
int a,d,e,f;
float b;
char c,ch;
printf("integer-a\nfloat-b\ncharacter-c\nENTER CHOICE=\n");
scanf("%c",&ch);
switch(ch)
{ case 'a': d=sizeof(a);
printf("size=%d\n",d);
break;
case 'b': e=sizeof(b);
printf("size=%d\n",e);
break;
case 'c': f=sizeof(c);
printf("size=%d\n",f);
break;
default:printf("wrong input\n");
}
getch();
}