0  DIM OP(13),N(13),X(13,1):READ OP(ZERO),N(ZERO),X(ZERO,0),X(ZERO,1):CN = CN + 1:DATA1,0,0,1
 1 C = ZERO:GOSUB 10:C=R:GOSUB 10:C=R:GOSUB 10:THREE = R
 2 C = THREE                         :GOSUB 10:FOUR  = R
 3 C = THREE                         :GOSUB 80:PRINT "THREE        -> "R
 4 C = FOUR                          :GOSUB 80:PRINT "FOUR         -> "R
 5 C = THREE:D = FOUR :GOSUB 50:C = R:GOSUB 80:PRINT "THREE + FOUR -> "R
 6 C = THREE:D = FOUR :GOSUB 60:C = R:GOSUB 80:PRINT "THREE * FOUR -> "R
 7 C = THREE:D = FOUR :GOSUB 70:C = R:GOSUB 80:PRINT "THREE ^ FOUR -> "R
 8 C = FOUR :D = THREE:GOSUB 70:C = R:GOSUB 80:PRINT "FOUR ^ THREE -> "R
 9 I = 5              :GOSUB 90:C = R:GOSUB 80:PRINT "5 -> FIVE    -> "R;:END
REM SUCC
 10 R = CN:OP(R) = OP(C):N(R) = N(C) + 1:X(R,0) = X(C,0):X(R,1) = X(C,1):CN = CN + 1:RETURN
REM SUM
 20  FOR I = 1 TO N:A = A + B:NEXT I:R = A:RETURN
REM MUL
 30  FOR I = 1 TO N:A = A * B:NEXT I:R = A:RETURN
REM POW
 40  FOR I = 1 TO N:A = A ^ B:NEXT I:R =  INT (A):RETURN
REM CHURCH SUM
 50 RES = CN:OP(RES) = 1:N(RES) = 1:X(RES,0) = N(C):X(RES,1) = N(D):CN = CN + 1:R = RES:RETURN
REM CHURCH MUL
 60 RES = CN:OP(RES) = 2:N(RES) = 1:X(RES,0) = N(C):X(RES,1) = N(D):CN = CN + 1:R = RES:RETURN
REM CHURCH POW
 70 RES = CN:OP(RES) = 3:N(RES) = 1:X(RES,0) = N(C):X(RES,1) = N(D):CN = CN + 1:R = RES:RETURN
REM CHURCH TO NUM
 80 N = N(C):A = X(C,0):B = X(C,1):ON OP(C) GOTO 20,30,40:STOP
REM NUM TO CHURCH
 90 R = ZERO:IF I = 0 THEN RETURN
 91 I = I - 1:GOSUB 90:C = R:GOTO 10"SUCC