find the number of pairs formed from given socks

Author: VikasChitturi

Ushur/findPairs.py

@@ -0,0 +1,25 @@
+"""
+Given a list of numbers and each number represents a different color of
+a sock, Find the number of pairs that can be formed from given list of
+socks
+
+"""
+
+import collections
+def find_pairs(n,socks):
+    num_pairs = 0
+    freqs = collections.Counter(socks)
+    for s,c in freqs.items():
+        if c >= 2:
+            num_pairs += (c//2)
+    return num_pairs
+
+
+if __name__ == '__main__':
+    N = 9
+    socks = [1,2,2,1,3,4,5,2,2]
+    print (find_pairs(N, socks))
+    
+    N = 10
+    socks = [1,1,2,1,3,4,5,2,2,0]
+    print (find_pairs(N, socks))