ABCDEFGHIJKLMNOPQRSTUVWXYZAA
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Make a copy of this sheets, by going to File->Make a copy
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Note that the key consists of lowercase letters, and has no repeated letters. It is 9 characters long. Order of characters matters!
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Key:abcdefg
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Ciphertext
Õ�ÜÑàÏ�ëÞåØäÑëÜÇÞÔå
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Plaintext
s/vi{c�|�p�e�{c{l�
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🚩 = flag{abcdefg}
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Hint: can you write an encryption algorithm that undoes the decryption algorithm below?
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abcdefg
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abcdefghijklmnopqrstuvwxyz
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abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz
Finding the right difference between ascii codes (hint: the value must be > 0, but less than 26. Why < 26?) Another hint: we repeat the alphabet at E26!
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1a a9732Õ213116t19451919s
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2b b983214547/#VALUE!#VALUE!#VALUE!#N/A/
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3c c9932Ü220121y22482222v
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4d d10032Ñ209109m93599i
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5e e10132à224123{#VALUE!#VALUE!#VALUE!#N/A{
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6f f10232Ï207105i32933c
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7g g1033213128-6-5-31#N/A
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8h a9732ë235138#VALUE!#VALUE!#VALUE!#N/A
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9i b9832Þ222124|#VALUE!#VALUE!#VALUE!#N/A|
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10j c9932å229130#VALUE!#VALUE!#VALUE!#N/A
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11k d10032Ø216116t16421616p
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12l e10132ä228127#VALUE!#VALUE!#VALUE!#N/A
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13m f10232Ñ209107k53155e
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14n g10332ë235132#VALUE!#VALUE!#VALUE!#N/A
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15o a9732Ü220123{#VALUE!#VALUE!#VALUE!#N/A{
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16p b9832Ç199101e32933c
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17q c9932Þ222123{#VALUE!#VALUE!#VALUE!#N/A{
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18r d10032Ô212112p12381212l
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19s e10132å229128#VALUE!#VALUE!#VALUE!#N/A
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20t