Practice · 10 problems

Math & Bits

0 of 10 solved on this device

1. 046Single NumberGiven a non-empty array where every element appears twice except for one, find that single element. Must run in O(n) time using O(1) extra space.Easy
2. 047Counting BitsGiven an integer `n`, return an array of length n + 1 where ans[i] is the number of 1-bits in the binary representation of i.Easy
3. 048Reverse IntegerGiven a signed 32-bit integer `x`, return x with its digits reversed. If reversing causes the value to fall outside [-2^31, 2^31 - 1], return 0.Medium
4. 049Pow(x, n)Implement pow(x, n), which computes x raised to the power n. `n` may be negative.Medium
5. 050Rotate ImageGiven an n x n 2D matrix representing an image, rotate it 90 degrees clockwise. You must rotate it IN PLACE — do not allocate another matrix.Medium
6. 088Number of 1 BitsWrite a function that takes an unsigned integer and returns its Hamming weight: the number of 1 bits in its binary representation.Easy
7. 089Missing NumberGiven an array `nums` containing n distinct numbers drawn from the range [0, n], return the one number in that range that is missing. Aim for O(n) time and O(1) extra space.Easy
8. 090Plus OneYou are given a large integer as an array of digits, most significant digit first, with no leading zeros. Increment it by one and return the resulting digit array.Easy
9. 127Reverse BitsReverse the bits of a given 32-bit unsigned integer and return the result.Easy
10. 128Sum of Two IntegersGiven two integers `a` and `b`, return their sum WITHOUT using the + or - operators.Medium