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+--- Day 4: Secure Container ---
+You arrive at the Venus fuel depot only to discover it's protected by a password. The Elves had written the password on a sticky note, but someone threw it out.
+
+However, they do remember a few key facts about the password:
+
+It is a six-digit number.
+The value is within the range given in your puzzle input.
+Two adjacent digits are the same (like 22 in 122345).
+Going from left to right, the digits never decrease; they only ever increase or stay the same (like 111123 or 135679).
+Other than the range rule, the following are true:
+
+111111 meets these criteria (double 11, never decreases).
+223450 does not meet these criteria (decreasing pair of digits 50).
+123789 does not meet these criteria (no double).
+How many different passwords within the range given in your puzzle input meet these criteria?
+
+Your puzzle answer was 1033.
+
+--- Part Two ---
+An Elf just remembered one more important detail: the two adjacent matching digits are not part of a larger group of matching digits.
+
+Given this additional criterion, but still ignoring the range rule, the following are now true:
+
+112233 meets these criteria because the digits never decrease and all repeated digits are exactly two digits long.
+123444 no longer meets the criteria (the repeated 44 is part of a larger group of 444).
+111122 meets the criteria (even though 1 is repeated more than twice, it still contains a double 22).
+How many different passwords within the range given in your puzzle input meet all of the criteria?
+
+Your puzzle answer was 670.
+
+Both parts of this puzzle are complete! They provide two gold stars: **
+
+At this point, you should return to your Advent calendar and try another puzzle.
+
+Your puzzle input was 254032-789860.
+
+You can also [Share] this puzzle.