From 53379c023fe935398801f41aad3dd0399b2d7d73 Mon Sep 17 00:00:00 2001 From: ZongqinWang <1722249371@qq.com> Date: Fri, 13 May 2022 17:28:14 +0800 Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200454.=E5=9B=9B=E6=95=B0?= =?UTF-8?q?=E7=9B=B8=E5=8A=A0II.md=20Scala=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0454.四数相加II.md | 36 +++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/problems/0454.四数相加II.md b/problems/0454.四数相加II.md index a6cd413b..d4aba8fa 100644 --- a/problems/0454.四数相加II.md +++ b/problems/0454.四数相加II.md @@ -318,5 +318,41 @@ impl Solution { } ``` +Scala: +```scala +object Solution { + // 导包 + import scala.collection.mutable + def fourSumCount(nums1: Array[Int], nums2: Array[Int], nums3: Array[Int], nums4: Array[Int]): Int = { + // 定义一个HashMap，key存储值，value存储该值出现的次数 + val map = new mutable.HashMap[Int, Int]() + // 遍历前两个数组，把他们所有可能的情况都记录到map + for (i <- nums1.indices) { + for (j <- nums2.indices) { + val tmp = nums1(i) + nums2(j) + // 如果包含该值，则对他的key加1，不包含则添加进去 + if (map.contains(tmp)) { + map.put(tmp, map.get(tmp).get + 1) + } else { + map.put(tmp, 1) + } + } + } + var res = 0 // 结果变量 + // 遍历后两个数组 + for (i <- nums3.indices) { + for (j <- nums4.indices) { + val tmp = -(nums3(i) + nums4(j)) + // 如果map中存在该值，结果就+=value + if (map.contains(tmp)) { + res += map.get(tmp).get + } + } + } + // 返回最终结果，可以省略关键字return + res + } +} +``` -----------------------