Program do count blanks, tabs and newlines. its not correct tell me where i'm wrong

Program do count blanks, tabs and newlines. its not correct tell me where
i'm wrong

#include <stdio.h>
int main(void)
{
int c, blank, tab, lines;
int till = 0;
blank = tab = lines = 0;
while(till == 0)
{
c = getchar();
switch(c)
{
case ' ' :
blank++;
case '\t' :
tab++;
case '\n' :
lines++;
case 'EOF' : /* warning: multi-character character constant
[-Wmultichar] */
till = 1;
}
}
printf("Blanks :%d Tab :%d Lines :%d\n", blank, tab, lines);
return 0;
}
While i compile this code it persist this error : warning: multi-character
character constant [-Wmultichar] and how can we use EOF in SWITCH.