题解HJ8 | #合并表记录#
合并表记录
https://www.nowcoder.com/practice/de044e89123f4a7482bd2b214a685201
import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Scanner; import java.util.Set; import java.util.stream.Collectors; // 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); Integer num = in.nextInt(); Map<Integer, Integer> map = new HashMap<>(); for (int i = 0; i < num; i++) { int index = in.nextInt(); int value = in.nextInt(); Set keySet = map.keySet(); if (keySet.contains(index)) { Integer existValue = map.get(index); existValue += value; map.remove(index); map.put(index, existValue); } else { map.put(index, value); } } List<Integer> keyList = map.keySet().stream().sorted().collect(Collectors.toList()); for (int i = 0; i < map.keySet().size(); i++) { System.out.println(keyList.get(i) + " " + map.get(keyList.get(i))); } } }
简单 希望机考题也能这么简单就拿下