BackdoorCTF2017 - No-Calm

nocalm.py

def loop(v1, v2, v3):
    for a in xrange(127):
        for b in xrange(127):
            for c in xrange(127):
                if b + a - c == v1 and a - b + c == v2 and b - a + c == v3:
                    return chr(a) + chr(b) + chr(c)
 
 output = []
 output.append(loop(81, 53, 87))
 output.append(loop(90, 156, 66))
 output.append(loop(98, 140, 92))
 output.append(loop(38, 170, 60))
 output.append(loop(29, 161, 69))
 output.append(loop(163, 27, 69))
 output.append(loop(147, 43, 59))
 output.append(loop(146, 86, 44))
 output.append(loop(67, 89, 75))
 output.append(loop(117, 125, 125))
 print "".join(output)