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+--- Day 10: Adapter Array ---
+
+Patched into the aircraft's data port, you discover weather forecasts of a massive tropical storm.
+Before you can figure out whether it will impact your vacation plans, however, your device suddenly
+turns off!
+
+Its battery is dead.
+
+You'll need to plug it in. There's only one problem: the charging outlet near your seat produces the
+wrong number of jolts. Always prepared, you make a list of all of the joltage adapters
+in your bag.
+
+Each of your joltage adapters is rated for a specific output joltage (your puzzle
+input). Any given adapter can take an input 1, 2, or 3 jolts lower than its rating and
+still produce its rated output joltage.
+
+In addition, your device has a built-in joltage adapter rated for 3 jolts higher than
+the highest-rated adapter in your bag. (If your adapter list were 3, 9, and 6, your device's
+built-in adapter would be rated for 12 jolts.)
+
+Treat the charging outlet near your seat as having an effective joltage rating of 0.
+
+Since you have some time to kill, you might as well test all of your adapters. Wouldn't want to get
+to your resort and realize you can't even charge your device!
+
+If you use every adapter in your bag at once, what is the distribution of joltage
+differences between the charging outlet, the adapters, and your device?
+
+For example, suppose that in your bag, you have adapters with the following joltage ratings:
+
+16 10 15 5 1 11 7 19 6 12 4
+
+With these adapters, your device's built-in joltage adapter would be rated for 19 + 3 =
+22 jolts, 3 higher than the highest-rated adapter.
+
+Because adapters can only connect to a source 1-3 jolts lower than its rating, in order to use every
+adapter, you'd need to choose them like this:
+
+- The charging outlet has an effective rating of 0 jolts, so the only adapters that could connect to
+it directly would need to have a joltage rating of 1, 2, or 3 jolts. Of these, only one you have is
+an adapter rated 1 jolt (difference of 1). - From your 1-jolt rated adapter, the only
+choice is your 4-jolt rated adapter (difference of 3). - From the 4-jolt rated adapter,
+the adapters rated 5, 6, or 7 are valid choices. However, in order to not skip any adapters, you
+have to pick the adapter rated 5 jolts (difference of 1). - Similarly, the next choices
+would need to be the adapter rated 6 and then the adapter rated 7 (with difference of 1
+and 1). - The only adapter that works with the 7-jolt rated adapter is the one rated 10
+jolts (difference of 3). - From 10, the choices are 11 or 12; choose 11 (difference of
+1) and then 12 (difference of 1). - After 12, only valid adapter has a
+rating of 15 (difference of 3), then 16 (difference of 1), then 19
+(difference of 3). - Finally, your device's built-in adapter is always 3 higher than
+the highest adapter, so its rating is 22 jolts (always a difference of 3).
+
+In this example, when using every adapter, there are 7 differences of 1 jolt and
+5 differences of 3 jolts.
+
+Here is a larger example:
+
+28 33 18 42 31 14 46 20 48 47 24 23 49 45 19 38 39 11 1 32 25 35 8 17 7 9 4 2 34 10 3
+
+In this larger example, in a chain that uses all of the adapters, there are 22
+differences of 1 jolt and 10 differences of 3 jolts.
+
+Find a chain that uses all of your adapters to connect the charging outlet to your device's built-in
+adapter and count the joltage differences between the charging outlet, the adapters, and your
+device. What is the number of 1-jolt differences multiplied by the number of 3-jolt
+differences?
+
+