From 80eb43f36d73826d8131b1febe95d8c33743083a Mon Sep 17 00:00:00 2001
From: nolanzzz <nolanwork131@gmail.com>
Date: Thu, 2 Sep 2021 23:51:43 -0400
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=20PHP=E7=89=88=E6=9C=AC?=
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---
 problems/0454.四数相加II.md | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/problems/0454.四数相加II.md b/problems/0454.四数相加II.md
index 4e61dc2f..9fe01ad1 100644
--- a/problems/0454.四数相加II.md
+++ b/problems/0454.四数相加II.md
@@ -220,7 +220,37 @@ var fourSumCount = function(nums1, nums2, nums3, nums4) {
 };
 ```
 
-
+PHP:
+```php
+class Solution {
+    /**
+     * @param Integer[] $nums1
+     * @param Integer[] $nums2
+     * @param Integer[] $nums3
+     * @param Integer[] $nums4
+     * @return Integer
+     */
+    function fourSumCount($nums1, $nums2, $nums3, $nums4) {
+        $map = [];
+        foreach ($nums1 as $n1) {
+            foreach ($nums2 as $n2) {
+                $temp = $n1 + $n2;
+                $map[$temp] = isset($map[$temp]) ? $map[$temp]+1 : 1;
+            }
+        }
+        $count = 0;
+        foreach ($nums3 as $n3) {
+            foreach ($nums4 as $n4) {
+                $temp = 0 - $n3 - $n4;
+                if (isset($map[$temp])) {
+                    $count += $map[$temp];
+                }
+            }
+        }
+        return $count;
+    }
+}
+```
 
 
 -----------------------