Mirror-machine

A Mirror-machine is an extremely simple program type invented by User:ReplayShells to check decision, addition, subtraction, loops, input and outputs. Process:

• Input vars a,b (b is unsigned.)
• Increment a
• Decrement b
• If a is not 0:
  • Print a
  • Set a to 0
• If b is not 1:
  • Print b
• While b is not 0
  • Print b
  • Decrement b
• Input a,b
• Print a - b
• Print ABC
• Terminate program

The program, when expressed in pseudocode, adheres to the following principles:

a ← input integer, where a ∈ ℤ
b ← input integer, where b ∈ ℤ ∧ b ≥ 0

a ← a + 1
b ← b - 1

if a ≠ 0 then
  print a
  a ← 0
end if

if b ≠ 1 then
  print b
end if

while b ≠ 0 do
  print b
  b ← b - 1
end while

a ← input integer, where a ∈ ℤ
b ← input integer, where b ∈ ℤ ∧ b ≥ 0

print a - b

print "ABC"
terminate program

Implementations

C

#include <stdio.h>
int main(void)
{
	int a;
	unsigned b;
	scanf("%d %u", &a, &b);
	++a;
	--b;
	if(a != 0)
	{
		printf("%d\n", a);
		a = 0;
	}
	if(b != 1)
		printf("%u\n", b);
	while(b != 0)
	{
		printf("%u\n", b);
		--b;
	}
	scanf("%d %u", &a, &b);
	printf("%d\n", a - b);
	printf("ABC\n");
	return 0;
}

Phile

OPEN "stdin.stream";
OPEN "stdout.stream";
OPEN "a";
OPEN "b";
/// Input variables a, b.
OVERWRITE "a" READ "stdin.stream";
OVERWRITE "b" READ "stdin.stream";
/// Increment a.
OVERWRITE "a" READ "a" + 1;
/// Decrement b.
OVERWRITE "b" READ "b" - 1;
/// Test of a.
READ  "a" = 0? 11;
OVERWRITE "stdout.stream" READ "a" + "\n";
OVERWRITE "a" 0;
/// Line 11:
/// Test of b.
READ  "b" = 1? 13;
OVERWRITE "stdout.stream" READ "b" + "\n";
/// Line 13:
/// While loop.
READ  "b" = 0? 17;
OVERWRITE "stdout.stream" READ "b" + "\n";
OVERWRITE "b" READ "b" - 1;
READ  "b" ! 0? 13;
/// Line 17:
/// Input a, b.
OVERWRITE "a" READ "stdin.stream";
OVERWRITE "b" READ "stdin.stream";
/// Print a - b.
OVERWRITE "stdout.stream" READ "a" - READ "b";
OVERWRITE "stdout.stream" "\n";
/// Print "ABC".
OVERWRITE "stdout.stream" "ABC" + "\n";
/// Terminate program.
CLOSE "stdin.stream";
CLOSE "stdout.stream";
CLOSE "a";
CLOSE "b";

Python

a, b = int(input()), int(input())

a += 1
b -= 1

if a != 0:
    print(a)
    a = 0

if b != 1:
    print(b)

while b != 0:
    print(b)
    b -= 1

a, b = int(input()), int(input())

print(a-b)

print("ABC")

Rec

R/R\
[1:^1:P0 1;0^]
[0:\^0:P0^]
[0:^0:P\]
R1;R0;
[0:^\1:\1;]
[^]P
65p 66p 67p