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Obsolete Programming

Statement

 Goal

How is your CSB ? Very bad, in fact, and you have been moved from the prestigious Bot Division to the awful Legacy Softwares Division where you must maintain obsolete and crappy code that runs 90% of your corporation's business.

Today you must write an interpreter for a strange and forgotten language, written in a narrow character set : only uppercase letters, digits, minus sign, space and newline.

Basically the language is based on RPN (Reverse Polish Notation) with the abilty to define new instructions.

Lines are split in instructions separated by space(s).

If the instruction is a number, simply put in on top of the stack.
The operations (ADD, SUB, MUL, DIV, MOD) pop the last two numbers out of the stack and push the result back on top.
For example after, 2 5 SUB 8, the stack is -3 8.
DIV is the integer quotient and MOD the remainder of the division.

There are also operators that act on the stack itself:
POP removes the top number.
DUP duplicates the top number.
SWP swaps the two top numbers. 4 5 SWP 6 swaps 4 and 5 then pushes 6 on top, the stack is 5 4 6.
ROT brings to the top the third number of the stack. If the stack is 1 2 3 4, ROT changes it in 1 3 4 2.
OVR copies the second top number of the stack on the top. If the stack is 1 2 3 4, OVR changes it in 1 2 3 4 3.

POS removes the top number, push 1 if this number is ≥ 0, otherwise push 0.
NOT removes the top number, push 1 if this number is 0, otherwise push 0.
OUT removes the top number and print it on the standard output, followed by a newline char.

To define a new instruction the syntax is :

DEF name RPN instructions END

The instructions between DEF and END are not executed immediately but stored to be executed when name appears as instruction outside, after its definition.
name must not be an already defined instruction or a number.
Note that name can appears in its own definition (recursion is available).

For example
DEF SQ DUP MUL END defines the instruction SQ
when 4 SQ appears, 4 is pushed on the stack, then DUP then MUL are executed.

Inside a definition, conditionals are available :

IF RPN instructions FI
remove the top number, if this number is not zero, the instructions between IF and FI are executed, and continue with instructions after FI. If the number is zero, the execution continues after FI.

IF RPN instructions 1 ELS RPN instructions 2 FI
Remove the top number, if this number is not zero, the instructions between IF and ELS are executed, and continue with instructions after FI. If the number is zero, the instructions between ELS and FI are executed and continue execution after FI.

The two conditional structures can be nested.
Input
Line 1: N : number of input lines of code
N lines: Obsolete code
Output
any number of lines: whatever the obsolet program outputs
Constraints
1 ≤ N ≤ 100
All the numbers are signed integer (minimum width : 30 bits).
All tests are correct (ie don't use undefined instruction) and use MOD and DIV instructions only with positive arguments.
Example
Input
6
10 5 ADD OUT
10 5 SUB OUT
12 24 SUB OUT
30 10 MUL OUT
50 7 DIV OUT
50 7 MOD OUT
Output
15
5
-12
300
7
1
Tags
Difficulty
Hard
Test cases
Arithmetic test Test
Input
6 10 5 ADD OUT 10 5 SUB OUT 12 24 SUB OUT 30 10 MUL OUT 50 7 DIV OUT 50 7 MOD OUT
Output
15 5 -12 300 7 1
Arithmetic test Validator
Input
6 5 5 ADD OUT 15 5 SUB OUT 100 240 SUB OUT 6 7 MUL OUT 98 13 DIV OUT 98 13 MOD OUT
Output
10 10 -140 42 7 7
Stack Manipulations Test
Input
4 101 200 854 POP SWP DUP OUT OUT OUT 9 76 100 ROT OUT OUT OUT 5 4 OVR OUT OUT OUT 0 1 4 ROT ROT DUP ROT ADD ROT OUT OUT OUT
Output
101 101 200 9 100 76 5 4 5 4 1 1
Stack Manipulations Validator
Input
4 18 20 OVR OUT OUT OUT 9 8 3 POP SWP DUP OUT OUT OUT 1001 11 13 ROT OUT OUT OUT 1 1 3 ROT ROT DUP ROT ADD ROT OUT OUT OUT
Output
18 20 18 9 9 8 1001 13 11 3 2 1
"Logic" Test
Input
5 401 13 NOT NOT OUT OUT 402 178 NOT OUT OUT 403 89 POS OUT OUT 404 0 POS OUT OUT 405 -56 POS OUT OUT
Output
1 401 0 402 1 403 1 404 0 405
"Logic" Validator
Input
5 -12 POS OUT 0 POS OUT 8 POS OUT 96 NOT OUT -8 NOT NOT OUT
Output
0 1 1 0 1
Simple function - square Test
Input
2 DEF SQ DUP MUL END 4 SQ OUT 10 SQ OUT 71 SQ OUT
Output
16 100 5041
Simple function - cubic Validator
Input
2 DEF TST DUP DUP MUL MUL END 2 TST OUT 17 TST OUT 9 TST OUT
Output
8 4913 729
Function and test Test
Input
4 DEF MAX OVR OVR SUB POS NOT IF SWP FI POP END 5 3 MAX 3 7 MAX MAX -2 MAX 4 MAX OUT -8 -3 -7 2 -4 MAX MAX MAX MAX OUT 0 1 MAX 13 MAX DUP OUT 20 MAX 7 MAX OUT
Output
7 2 13 20
Function and test Validator
Input
4 DEF TST OVR OVR SUB POS IF SWP FI POP END 5 3 TST 3 7 TST TST -2 TST 4 TST OUT -8 -3 -7 2 -4 TST TST TST TST OUT 0 1 TST 13 TST DUP OUT 20 TST -3 TST OUT
Output
-2 -8 0 -3
Function calling function and nested if Test
Input
17 DEF ABS DUP POS NOT IF 0 SWP SUB FI END 51 ABS OUT -5 ABS OUT 0 ABS OUT DEF NZ OVR ABS OVR ABS SUB DUP NOT IF POP DUP POS IF SWP FI ELS POS IF SWP FI FI POP END 1 -2 NZ -8 NZ 4 NZ 5 NZ OUT -12 -5 NZ -137 NZ OUT 42 -5 NZ 12 NZ 21 NZ 5 NZ 24 NZ OUT 42 5 NZ 12 NZ 21 NZ -5 NZ 24 NZ OUT -5 -4 NZ -2 12 NZ NZ -40 4 NZ 2 18 NZ NZ NZ 11 5 NZ NZ OUT
Output
51 5 0 1 -5 5 5 2
Function calling function and nested if Validator
Input
10 DEF T0 DUP POS NOT IF 0 SWP SUB FI END DEF TST OVR T0 OVR T0 SUB DUP NOT IF POP DUP POS IF SWP FI ELS POS IF SWP FI FI POP END 7 -10 TST 13 1 TST TST -1 8 TST TST OUT 3 -5 TST 13 4 TST TST -1 8 TST TST OUT 4 -10 TST 13 -4 TST TST -5 8 TST TST OUT
Output
1 -1 4
the Queen of functions Test
Input
5 DEF F1 DUP 2 SUB POS IF DUP 1 SUB F1 MUL ELS POP 1 FI END 7 F1 OUT 10 F1 OUT 0 F1 OUT 3 F1 OUT
Output
5040 3628800 1 6
the Queen of functions Validator
Input
5 DEF TST DUP POS IF DUP 1 SUB TST ADD ELS POP 0 FI END 7 TST OUT 10 TST OUT 1 TST OUT 3 TST OUT
Output
28 55 1 6
I have no loop and I must iterate Test
Input
8 DEF SQ DUP MUL END DEF PL DUP OUT SQ OUT END DEF PR OVR PL SWP 1 ADD OVR OVR SUB POS IF SWP PR ELS POP POP FI END 1 5 PR 30 33 PR
Output
1 1 2 4 3 9 4 16 5 25 30 900 31 961 32 1024 33 1089
I have no loop and I must iterate Validator
Input
6 DEF TST OVR DUP OUT DUP DUP MUL MUL OUT SWP 1 ADD OVR OVR SUB POS IF SWP TST ELS POP POP FI END 1 5 TST 30 33 TST
Output
1 1 2 8 3 27 4 64 5 125 30 27000 31 29791 32 32768 33 35937
Hello Fibonacci ! Test
Input
6 DEF RFIB DUP IF 1 SUB ROT ROT DUP ROT ADD ROT RFIB ELS POP POP FI END DEF FIB 0 1 ROT RFIB END 5 FIB OUT 6 FIB OUT 2 FIB OUT 10 FIB OUT
Output
5 8 1 55
Hello Lucas ! Validator
Input
6 DEF TST DUP IF 1 SUB ROT ROT DUP ROT ADD ROT TST ELS POP POP FI END 2 1 0 TST OUT 2 1 9 TST OUT 2 1 5 TST OUT 2 1 7 TST OUT
Output
2 76 11 29
Integer square root Test
Input
20 DEF ESTIM DUP 4 SUB POS IF 4 DIV SWP 2 MUL SWP ESTIM ELS POP FI END DEF NA SWP OVR DIV ADD 2 DIV END DEF RS OVR OVR NA OVR OVR SUB DUP 1 SUB MUL IF SWP POP RS ELS ROT POP OVR OVR SUB POS IF SWP FI POP FI END DEF ASQRT DUP 1 SWP ESTIM RS END 5040 ASQRT OUT 10 ASQRT OUT 1001 ASQRT OUT 65000 ASQRT OUT
Output
70 3 31 254
Integer cubic root Validator
Input
17 DEF T0 DUP 8 SUB POS IF 8 DIV SWP 2 MUL SWP T0 ELS POP FI END DEF T2 SWP OVR DIV OVR DIV SWP 2 MUL ADD 3 DIV END DEF T1 OVR OVR T2 OVR OVR SUB DUP 1 SUB MUL IF SWP POP T1 ELS ROT POP OVR OVR SUB POS IF SWP FI POP FI END DEF TST DUP 1 SWP T0 T1 END 5040 TST OUT 10 TST OUT 1001 TST OUT 65000 TST OUT
Output
17 2 10 40
Solution language
Solution
Stub generator input
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