Today, the elves are placing some more caches. One elf has written some notes down, but the computer has saved them as an image! Furthermore, the image has been corrupted! The image is represented as 9 different grids, each grid denoting a layer of the binary. The pixel in each position on the grids has a binary code read from the top grid to the bottom. If the checksum of the pixel is correct, it is a black pixel, else it is a white pixel. The checksum is calculated using parity bits. Each binary byte needs to have an even number of 1s. This is equivalent to calculating the bitwise XOR of each bit. The parity bit is the bit in the bottom (9th) grid. What does the image say (all caps, no spaces)? Here is your test input:
00100111011 10010100000 10111011110 01001110101 11011010000 01111010110 10100111001 00111011000 11110111110 10011101010 01011011011 01110010010 11111001111 00011011011 10111000001 11011110110 00111010011 01011100111 10010010000 00010101110 10010010010 00001111001 10001101011 01000011100 11010100100 11100111100 01111111101 11110001001 10010101011 01111010101 00101001110 00010001110 00001011100 11110011011 10100011110 00111110100
AOC
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