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function bigadd$(bignum1$,bignum2$)
	lookup$ = "01234567890123456789"
	bn1len = len(bignum1$)
	bn2len = len(bignum2$)
	bnwork$=""
	` Find the longest of the two numbers for our loop
	if bn1len<>bn2len
		if bn1len > bn2len 
			maxlen = bn1len
			` pad shorter string with leading zero
			for t2 = 1 to maxlen-bn2len
				bnwork$ = bnwork$ + "0"
			next t2
			bignum2$ = bnwork$ + bignum2$
		elseif bn1len < bn2len
			maxlen = bn2len
			` pad shorter string with leading zero
			for t2 = 1 to maxlen-bn1len
				bnwork$ = bnwork$ + "0"
			next t2
			bignum1$ = bnwork$ + bignum1$
		endif
	else
		maxlen = bn1len
	endif
	for t = maxlen to 1 step -1
		offset = val(mid(bignum1$,t,1))+val(mid(bignum2$,t,1))
		resultchar$ = mid(lookup$,offset+carry+1,1)
		result$=result$+resultchar$
		if offset+carry >9
			carry = 1
		else
			carry = 0
		endif
	next t
	` Take care of the final carry
	if carry = 1
		result$=result$+"1"
		inc maxlen
	endif
	` flip the result so it is the right way round
	for t = 0 to maxlen
		properresult$ = properresult$ + mid(result$,maxlen-t,1)
	next t	
		
endfunction properresult$

test$ = bigadd$("4599549544412345678912345151413253421234","1000000000012817234681744012345678901234")
Print(test$)
Print(bigadd$("12345","12345"))

		valueA=10150
		valueB=266

		print hex$(ValueA+ValueB)

		LowByteSum=0
		HighByteSum=0

		// add the input values as if we only had an 8bit addition operator.
		LowByteSum=(ValueA and 255) + (ValueB and 255)	
		if LowByteSum>255
				// add the overflow
				HighByteSum=(LowByteSum >> 8)
		endif

		// shift the input byte sequence down
		ValueA=ValueA>>8
		ValueB=ValueB>>8

		// add the high bytes together
		HighByteSum+=(ValueA and 255) + (ValueB and 255)	

		if HighByteSum>255
				print "boom value bigger than 16bit.. sorry your cpu exploded!"
		endif

		print hex$(HighByteSum)+hex$(LowByteSum)
		

		Sync
		waitkey

 function bigmultiply(A$,B$)
 C$ = ""
 D$ = "0"
 FOR I =  LEN (B$) TO 1 STEP  - 1
	C = 0
	B =  VAL ( MID(B$,I,1))
    FOR J =  LEN (A$) TO 1 STEP  - 1
		V = B *  VAL ( MID(A$,J,1)) + C
		C =  V / 10
		V = V - C * 10
		C$ =  STR(V) + C$
	NEXT J
	IF C THEN C$ =  STR(C) + C$
	D$ = bigadd$(c$,d$)
	
	C$ = "0"
	J =  LEN (B$) - I
	While J
		J = J - 1
		C$ = C$ + "0"
	endwhile
 NEXT I
 endfunction D$

 function bigadd$(c$,d$)
 E =  LEN (D$)
 ERES$ = ""
 C = 0
 FOR J =  LEN (C$) TO 1 STEP  - 1
	IF E THEN D =  VAL ( MID(D$,E,1))
	V =  VAL ( MID(C$,J,1)) + D + C
	C = V > 9
	V = V - 10 * C
	ERES$ =  STR(V) + ERES$
	IF E 
		E = E - 1
		D = 0
	endif
NEXT J
while E
	V =  VAL ( MID(D$,E,1)) + C
	C = V > 9
	V = V - 10 * C
	ERES$ =  STR(V) + ERES$
	E = E - 1
endwhile
	if C = 1
		ERES$="1"+ERES$
	endif
endfunction ERES$