Create 1512. Number of Good Pairs

algorithms/Python/Easy/1512. Number of Good Pairs

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+/*
+Given an array of integers nums.
+
+A pair (i,j) is called good if nums[i] == nums[j] and i < j.
+
+Return the number of good pairs.
+
+
+
+Example 1:
+
+Input: nums = [1,2,3,1,1,3]
+Output: 4
+Explanation: There are 4 good pairs (0,3), (0,4), (3,4), (2,5) 0-indexed.
+Example 2:
+
+Input: nums = [1,1,1,1]
+Output: 6
+Explanation: Each pair in the array are good.
+Example 3:
+
+Input: nums = [1,2,3]
+Output: 0
+
+
+Constraints:
+
+1 <= nums.length <= 100
+1 <= nums[i] <= 100
+*/
+
+class Solution:
+    def numIdenticalPairs(self, nums: List[int]) -> int: #{
+        num_dict = {}
+        for i in nums: #{
+            if str(i) in num_dict.keys():
+                num_dict[str(i)] += 1        
+            else: num_dict[str(i)] = 1
+        #}
+        res = 0
+        for value in num_dict.values(): #{
+            for i in range(1, value): #{
+                res+=i   
+            #}
+        #}
+        return res
+    #}
+