10 INPUT N
20 LET A=0
30 LET B=1
40 GOSUB 70
50 PRINT B
60 STOP
70 IF N=1 THEN RETURN
80 LET C=B
90 LET B=A+B
100 LET A=C
110 LET N=N-1
120 GOSUB 70
130 RETURN