The true test of problem solving: when one realizes that time and memory aren’t infinite.
My answers available using Java on GitHub:
https://github.com/mirhoseini/hacker_rank
Spoil Danger!!! 
passed all test cases including:
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Solve me first
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Solve me second
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Flipping bits
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Utopian Tree
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Maximizing XOR
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Alternating Characters
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The Love-Letter Mystery
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Angry Children
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Game of Thrones – I
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ACM ICPC Team
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Filling Jars
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Chocolate Feast
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Sherlock and Squares
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Halloween party
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Manasa and Stones
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Sherlock and GCD
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Sherlock and The Beast
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Find Digits
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Is Fibo
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