Any length number adder

10 text : pr#0

0 rem Numbers to add:
20 n1$ = "1946284628648198247651913"
30 n2$ = "8175832638363856421903252"

0 rem Make numbers same length by adding 0's at the start
40 if len(n2$) < len(n1$) then n2$ = "0" + n2$ : goto 40
50 if len(n1$) < len(n2$) then n1$ = "0" + n1$ : goto 50

0 rem Add numbers:
100 for x = len(n1$) to 1 step -1
110 n = val(mid$(n1$,x,1)) + val(mid$(n2$,x,1)) + c
115 c = 0 : rem
120 if n > 9 then c = 1 : n = n - 10 : rem (c)arry
130 f$ = str$(n) + f$
140 next

0 rem Add the final "1" if needed:
145 if c = 1 then f$ = "1" + f$

0 rem Print:
150 ? n1$:?"+":?n2$:?"=":?f$