New May problem done

problems/387/main.py

+class Solution:
+    def firstUniqChar(self, s):
+        seen = dict()
+        for x in range(len(s)):
+            if s[x] in seen:
+                seen[s[x]][0] += 1
+            else:
+                seen[s[x]] = [1, x]
+        
+        result = None
+        for key, val in seen.items():
+            if val[0] == 1 and (result is None or val[1] < result):
+                result = val[1]
+                
+        if result is None:
+            return -1
+        
+        return result
+                
+s = Solution()
+print("Expected: 0")
+print("Got:", s.firstUniqChar("leetcode"))

problems/387/problem.txt

+Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1.
+
+Examples:
+
+s = "leetcode"
+return 0.
+
+s = "loveleetcode",
+return 2.
+
+Note: You may assume the string contain only lowercase letters. 

problems/387/run.sh

+#!/bin/bash
+
+python3 main.py