Package g2101_2200.s2166_design_bitset

Class Bitset

  • public class Bitset
extends Object
    2166 - Design Bitset\. Medium A **Bitset** is a data structure that compactly stores bits. Implement the `Bitset` class: * `Bitset(int size)` Initializes the Bitset with `size` bits, all of which are `0`. * `void fix(int idx)` Updates the value of the bit at the index `idx` to `1`. If the value was already `1`, no change occurs. * `void unfix(int idx)` Updates the value of the bit at the index `idx` to `0`. If the value was already `0`, no change occurs. * `void flip()` Flips the values of each bit in the Bitset. In other words, all bits with value `0` will now have value `1` and vice versa. * `boolean all()` Checks if the value of **each** bit in the Bitset is `1`. Returns `true` if it satisfies the condition, `false` otherwise. * `boolean one()` Checks if there is **at least one** bit in the Bitset with value `1`. Returns `true` if it satisfies the condition, `false` otherwise. * `int count()` Returns the **total number** of bits in the Bitset which have value `1`. * `String toString()` Returns the current composition of the Bitset. Note that in the resultant string, the character at the ith index should coincide with the value at the ith bit of the Bitset. **Example 1:** **Input** ["Bitset", "fix", "fix", "flip", "all", "unfix", "flip", "one", "unfix", "count", "toString"] [[5], [3], [1], [], [], [0], [], [], [0], [], []] **Output:** [null, null, null, null, false, null, null, true, null, 2, "01010"] **Explanation:** Bitset bs = new Bitset(5); // bitset = "00000". bs.fix(3); // the value at idx = 3 is updated to 1, so bitset = "00010". bs.fix(1); // the value at idx = 1 is updated to 1, so bitset = "01010". bs.flip(); // the value of each bit is flipped, so bitset = "10101". bs.all(); // return False, as not all values of the bitset are 1. bs.unfix(0); // the value at idx = 0 is updated to 0, so bitset = "00101". bs.flip(); // the value of each bit is flipped, so bitset = "11010". bs.one(); // return True, as there is at least 1 index with value 1. bs.unfix(0); // the value at idx = 0 is updated to 0, so bitset = "01010". bs.count(); // return 2, as there are 2 bits with value 1. bs.toString(); // return "01010", which is the composition of bitset. **Constraints:** * 1 <= size <= 105 * `0 <= idx <= size - 1` * At most 105 calls will be made **in total** to `fix`, `unfix`, `flip`, `all`, `one`, `count`, and `toString`. * At least one call will be made to `all`, `one`, `count`, or `toString`. * At most `5` calls will be made to `toString`.

    • Constructor Detail

      • Bitset

        public Bitset​(int size)

    • Method Detail

      • fix

        public void fix​(int idx)

      • unfix

        public void unfix​(int idx)

      • flip

        public void flip()

      • all

        public boolean all()

      • one

        public boolean one()

      • count

        public int count()