feat: add php solution to lc problem: No.1732 (doocs#1035)

Author: Qiu-IT

solution/1700-1799/1732.Find the Highest Altitude/README.md

@@ -179,6 +179,25 @@ int largestAltitude(int *gain, int gainSize) {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $gain
+     * @return Integer
+     */
+    function largestAltitude($gain) {
+        $max = 0;
+        for ($i = 0; $i < count($gain); $i++) {
+            $tmp += $gain[$i];
+            if ($tmp > $max) $max = $tmp;
+        }
+        return $max;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1700-1799/1732.Find the Highest Altitude/README_EN.md

@@ -149,6 +149,25 @@ int largestAltitude(int *gain, int gainSize) {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param Integer[] $gain
+     * @return Integer
+     */
+    function largestAltitude($gain) {
+        $max = 0;
+        for ($i = 0; $i < count($gain); $i++) {
+            $tmp += $gain[$i];
+            if ($tmp > $max) $max = $tmp;
+        }
+        return $max;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1700-1799/1732.Find the Highest Altitude/Solution.php

@@ -0,0 +1,14 @@
+class Solution {
+    /**
+     * @param Integer[] $gain
+     * @return Integer
+     */
+    function largestAltitude($gain) {
+        $max = 0;
+        for ($i = 0; $i < count($gain); $i++) {
+            $tmp += $gain[$i];
+            if ($tmp > $max) $max = $tmp;
+        }
+        return $max;
+    }
+}