commit 48189cdb564f2a4fc79299202cdd3eee05611a42
Author: Felix C. Stegerman <flx@obfusk.net>
Date:   Sat Sep 24 12:51:18 2016 +0200

    ...

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b144e43
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+/[a-z]
+
+*~
+*.swp
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..51259e2
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+CXXFLAGS=-Wall -Wextra -std=c++11
+SHELL=bash
+
+.PHONY: run
+
+run:
+	make $$P && { head $$S.in | cut -c-80 ; echo ; \
+	              time ./$$P < $$S.in ; echo \
+	              cat $$S.ans ; echo ; \
+	              diff -Naur <( ./$$P < $$S.in ) $$S.ans ; }
+
+run_py:
+	head $$S.in | cut -c-80 ; echo ; \
+	time python $$P.py < $$S.in ; echo \
+	cat $$S.ans ; echo ; \
+	diff -Naur <( python $$P.py < $$S.in ) $$S.ans
diff --git a/c.py b/c.py
new file mode 100644
index 0000000..bb0f306
--- /dev/null
+++ b/c.py
@@ -0,0 +1,25 @@
+from __future__ import print_function
+import sys
+
+a = map(int, sys.stdin.readline().split())
+b = map(int, sys.stdin.readline().split())
+c = map(int, sys.stdin.readline().split())
+
+def mul(a, b):
+  x,y = a; z,w = b
+  return x*z + y*w
+def add(a, b):
+  x,y = a; z,w = b
+  return (x+z, y+w)
+def sub(a, b):
+  x,y = a; z,w = b
+  return (x-z, y-w)
+
+if mul(sub(b, a), sub(c, a)) == 0:
+  print(*sub(add(c, b), a))
+elif mul(sub(a, b), sub(c, b)) == 0:
+  print(*sub(add(a, c), b))
+elif mul(sub(b, c), sub(a, c)) == 0:
+  print(*sub(add(a, b), c))
+else:
+  print("WTF")