[CSAW CTF Finals 2017] Rusty Road

rusty_road.py

from pwn import *

h ={"U":[[] for i in xrange(10)], "D":[[] for i in xrange(10)], "L":[[] for i in xrange(10)], "R":[[] for i in xrange(10)]}

U = open("U","rb")
D = open("D","rb")
L = open("L","rb")
R = open("R","rb")

for i in xrange(10):
    for j in xrange(0x10):
        h["U"][i].append(u32(U.read(4)))

for i in xrange(10):
    for j in xrange(0x10):
        h["D"][i].append(u32(D.read(4)))

for i in xrange(10):
    for j in xrange(0x10):
        h["L"][i].append(u32(L.read(4)))

for i in xrange(10):
    for j in xrange(0x10):
        h["R"][i].append(u32(R.read(4)))
def f(dirn, x, y):
    return h[dirn][y][x]

def get_sum(s):
    x, y = 0, 0
    pathsum = 2
    for i in s:
        # print pathsum
        if i == "U":
            y += 1
            y %= 10
        elif i == "D":
            if y > 0:
                y -= 1        
        elif i == "R":
            x += 1
            x %= 10
        elif i == "L":
            if x > 0:
                x -= 1
        pathsum += f(i,x,y)
    return pathsum

from itertools import *
for i in product("UR",repeat=18):
    if get_sum(i) == 0x622c and i.count("U")==i.count("R"):
        print ''.join(i)