the maximum value is 100Instead of a switch statement in keypad( ), use an array, a look-up-table.
This is much more simple and efficient.
WOW very good idea on the array
now we remove the keypad function and add
int keypad[]={0,55,56,57,0,52,53,54,0,49,50,51,0,13,48,46,0} ;
i tested it
it give the same output ,wrong output
if i type 13.3 it gives output 10