meowcat:
but for the next switch, when I press 4 or other key, nothing happen..so I assume that this getKey() not working in switch..key = keypad.getKey();
if (key != NO_KEY)
{
switch (key)
...
// when I press 4 or other key, nothing happen..
// so I assume that this getKey() not working in switch..
key = keypad.getKey();
I said before "don't do two getKeys". You are doing two getKeys. Please review my earlier answer as to why.
As for the answer, you could turn the answer into ASCII like this:
answer = i + j + '0';