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Bit manipulation problems in Python

Work with the binary digits of integers in Python, on problems with tests that check your answer at once.

Start with Power of Two

Beginner

  1. 31. Power of TwoIs this number made by doubling 1 again and again?30 XP4 min
  2. 216. Count the One BitsHow many switches are on inside this number?30 XP5 min
  3. 223. Read a Binary NumberWhat number is hiding in a row of ones and zeros?30 XP6 min

Intermediate

  1. 59. Gray Code SequenceCount through every binary number, flipping only one bit at a time60 XP12 min
  2. 74. Reverse the BitsRead a 32-bit number in the mirror65 XP10 min
  3. 325. Total Hamming DistanceCompare every pair of numbers bit by bit and count the differences75 XP14 min
  4. 327. Two Numbers Without a PartnerEveryone arrived in pairs except two loners: find them75 XP14 min
  5. 333. Total of Every Subset's XORCombine every possible group of numbers and add up the results80 XP15 min

Advanced

  1. 140. Decode the XOR ChainRebuild a shuffled list from the XORs of its neighbours130 XP25 min
  2. 347. Counting in Base Minus TwoWrite any whole number, negatives too, with only 0s and 1s and no minus sign120 XP22 min
  3. 412. Maximum XOR of Two NumbersFind the two numbers whose bits clash the most150 XP30 min

Expert

  1. 439. Numbers With Exactly K One BitsUp to a billion billion: how many numbers have exactly k bits switched on?210 XP35 min
  2. 454. Free the Chinese RingsAn old puzzle of rings on a bar, and the fewest moves that free every ring230 XP45 min
  3. 455. How Many Different XORsCountless ways to pick numbers, but how many different results do they make?230 XP40 min

Other topics

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