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+--- Part Two ---
+
+The final step in breaking the XMAS encryption relies on the invalid number you just found: you must
+find a contiguous set of at least two numbers in your list which sum to the invalid
+number from step 1.
+
+Again consider the above example:
+
+35 20 15 25 47 40 62 55 65 95 102 117 150 182
+127 219 299 277 309 576
+
+In this list, adding up all of the numbers from 15 through 40 produces the invalid number from step
+1, 127. (Of course, the contiguous set of numbers in your actual list might be much longer.)
+
+To find the encryption weakness, add together the smallest and
+largest number in this contiguous range; in this example, these are 15 and 47,
+producing 62.
+
+What is the encryption weakness in your XMAS-encrypted list of numbers?
+
+