题解 | #合并表记录#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        // while (in.hasNextInt()) { // 注意 while 处理多个 case
        //     int a = in.nextInt();
        //     int b = in.nextInt();
        //     System.out.println(a + b);
        // }
        int len = Integer.parseInt(in.nextLine());
        Main.Map[] table = new Main.Map[len];
        int index = 0;
        // HashMap<int, int> map = new HashMap<>();
        for (int i = 0; i < len; i++) {
            String line = in.nextLine();
            String[] entryStr = line.split(" ");
            int[] entry = new int[2];
            entry[0] = Integer.parseInt(entryStr[0]);
            entry[1] = Integer.parseInt(entryStr[1]);
            // Main main = new Main();
            int hasInd = 0;
            boolean has = false;
            int ind = 0;
            if (index == 0) {
                Main.Map map = new Main.Map(entry[0], entry[1]);
                table[ind] = map;
                index++;
                continue;
            }
            for (int j = index - 1; j >= 0; j--) {
                if (table[j].getKey() == entry[0]) {
                    hasInd = j;
                    has = true;
                    break;
                }
            }
            if (has) {
                table[hasInd].setValue(table[hasInd].getValue() + entry[1]);
            } else {

                for (int k = index; k >= 0; k--) {
                    if (k == 0) {
                        ind = 0;
                    } else if (table[k - 1].getKey() > entry[0]) {
                        table[k] = table[k - 1];
                    } else {
                        ind = k;
                        break;
                    }
                }
                Main.Map map = new Main.Map(entry[0], entry[1]);
                table[ind] = map;
                index++;

            }

        }
        for (int i = 0; i < index; i++) {
            System.out.println(table[i].getKey() + " " + table[i].getValue());
        }
    }
    static class Map {
        private int k;
        private int v;

        public Map(int k, int v) {
            this.k = k;
            this.v = v;
        }
        public int getKey() {
            return k;
        };
        public int getValue() {
            return v;
        };
        public void setValue(int v) {
            this.v = v;
        }
    }
}