1 REM PI CALCULATOR, B. WATSON, URCHLAY AT SLACKWARE.UK
3 REM PORTED FROM PYTHON3, FROM "LEARNPYTHON" PROJECT ON GITHUB
5 REM THE PYTHON VERSION IS MIT-LICENSED.
10 PRINT "CALCULATE HOW MANY DIGITS OF PI";
20 INPUT P
25 LET P=INT(P)
30 IF P>=1 THEN 60
40 PRINT "PLEASE ENTER A POSITIVE NUMBER."
50 GOTO 10
60 IF P<20 THEN 100
70 PRINT "WARNING: PROGRAM ONLY ACCURATE TO 20 DIGITS OR SO."
100 LET Q=1
110 LET R=0
120 LET T=1
130 LET K=1
140 LET N=3
150 LET L=3
160 LET C=0
200 IF (4*Q+R-T)>=(N*T) THEN 300
210 PRINT N;
215 IF C>0 THEN 220
217 PRINT ".";
220 LET C=C+1
230 IF C=P THEN 500
240 LET R1=10*(R-N*T)
250 LET N=INT((10*(3*Q+R))/T)-10*N
260 LET Q=Q*10
270 LET R=R1
280 GOTO 200
300 LET R1=(2*Q+R)*L
310 LET N1=INT((Q*(7*K)+2+(R*L))/(T*L))
320 LET Q=Q*K
330 LET T=T*L
340 LET L=L+2
350 LET K=K+1
360 LET N=N1
370 LET R=R1
380 GOTO 200
500 PRINT
510 REM THE PRINT ABOVE IS NEEDED TO MAKE MINIMALBASIC FLUSH ITS
520 REM OUTPUT BUFFER. OTHERWISE WE GET NO OUTPUT!
9999 END