g1601_1700.s1656_design_an_ordered_stream.OrderedStream Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of leetcode-in-java21 Show documentation

Java-based LeetCode algorithm problem solutions, regularly updated

There is a newer version: 1.38

package g1601_1700.s1656_design_an_ordered_stream;

// #Easy #Array #Hash_Table #Design #Data_Stream
// #2022_04_23_Time_95_ms_(74.07%)_Space_84.5_MB_(69.74%)

import java.util.ArrayList;
import java.util.List;

/**
 * 1656 - Design an Ordered Stream\.
 *
 * Easy
 *
 * There is a stream of `n` `(idKey, value)` pairs arriving in an **arbitrary** order, where `idKey` is an integer between `1` and `n` and `value` is a string. No two pairs have the same `id`.
 *
 * Design a stream that returns the values in **increasing order of their IDs** by returning a **chunk** (list) of values after each insertion. The concatenation of all the **chunks** should result in a list of the sorted values.
 *
 * Implement the `OrderedStream` class:
 *
 * *   `OrderedStream(int n)` Constructs the stream to take `n` values.
 * *   `String[] insert(int idKey, String value)` Inserts the pair `(idKey, value)` into the stream, then returns the **largest possible chunk** of currently inserted values that appear next in the order.
 *
 * **Example:**
 *
 * **![](https://assets.leetcode.com/uploads/2020/11/10/q1.gif)**
 *
 * **Input** ["OrderedStream", "insert", "insert", "insert", "insert", "insert"]
 *
 * [[5], [3, "ccccc"], [1, "aaaaa"], [2, "bbbbb"], [5, "eeeee"], [4, "ddddd"]]
 *
 * **Output:** [null, [], ["aaaaa"], ["bbbbb", "ccccc"], [], ["ddddd", "eeeee"]]
 *
 * **Explanation:**
 *
 *     // Note that the values ordered by ID is ["aaaaa", "bbbbb", "ccccc", "ddddd", "eeeee"].
 *     OrderedStream os = new OrderedStream(5);
 *     os.insert(3, "ccccc"); // Inserts (3, "ccccc"), returns [].
 *     os.insert(1, "aaaaa"); // Inserts (1, "aaaaa"), returns ["aaaaa"].
 *     os.insert(2, "bbbbb"); // Inserts (2, "bbbbb"), returns ["bbbbb", "ccccc"].
 *     os.insert(5, "eeeee"); // Inserts (5, "eeeee"), returns [].
 *     os.insert(4, "ddddd"); // Inserts (4, "ddddd"), returns ["ddddd", "eeeee"].
 *     // Concatentating all the chunks returned:
 *     // [] + ["aaaaa"] + ["bbbbb", "ccccc"] + [] + ["ddddd", "eeeee"] = ["aaaaa", "bbbbb", "ccccc", "ddddd", "eeeee"]
 *     // The resulting order is the same as the order above. 
 *
 * **Constraints:**
 *
 * *   `1 <= n <= 1000`
 * *   `1 <= id <= n`
 * *   `value.length == 5`
 * *   `value` consists only of lowercase letters.
 * *   Each call to `insert` will have a unique `id.`
 * *   Exactly `n` calls will be made to `insert`.
**/
public class OrderedStream {
    private String[] str;
    private int ptr = 0;

    public OrderedStream(int n) {
        this.str = new String[n];
    }

    public List insert(int idKey, String value) {
        this.str[idKey - 1] = value;
        List list = new ArrayList<>();
        while (ptr < str.length && str[ptr] != null) {
            list.add(str[ptr]);
            ptr++;
        }
        return list;
    }
}

/*
 * Your OrderedStream object will be instantiated and called as such:
 * OrderedStream obj = new OrderedStream(n);
 * List param_1 = obj.insert(idKey,value);
 */