From b7ea55c93b68391ecd87c39c06e2811f0ed6b98f Mon Sep 17 00:00:00 2001
From: Winson Huang <winsonhuang843@gmail.com>
Date: Tue, 18 Apr 2023 21:07:54 +0800
Subject: [PATCH] =?UTF-8?q?Update=200454.=E5=9B=9B=E6=95=B0=E7=9B=B8?=
 =?UTF-8?q?=E5=8A=A0II.md?=
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修改 Java 语言版本代码，让 HashMap 相关操作更简洁
---
 problems/0454.四数相加II.md | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/problems/0454.四数相加II.md b/problems/0454.四数相加II.md
index 411b60e8..abfc7c23 100644
--- a/problems/0454.四数相加II.md
+++ b/problems/0454.四数相加II.md
@@ -102,21 +102,14 @@ class Solution {
         //统计两个数组中的元素之和，同时统计出现的次数，放入map
         for (int i : nums1) {
             for (int j : nums2) {
-                int tmp = map.getOrDefault(i + j, 0);
-                if (tmp == 0) {
-                    map.put(i + j, 1);
-                } else {
-                    map.replace(i + j, tmp + 1);
-                }
+                int sum = i + j;
+                map.put(sum, map.getOrDefault(sum, 0) + 1);
             }
         }
         //统计剩余的两个元素的和，在map中找是否存在相加为0的情况，同时记录次数
         for (int i : nums3) {
             for (int j : nums4) {
-                int tmp = map.getOrDefault(0 - i - j, 0);
-                if (tmp != 0) {
-                    res += tmp;
-                }
+                res += map.getOrDefault(0 - i - j, 0);
             }
         }
         return res;