feat(smallest-common-num): add smallest common num challenge)

Author: jordanpaulchan

smallest-common-num/smallest-common-num.py

@@ -0,0 +1,42 @@
+"""
+Problem: Find smallest common number in list of sorted arrays.
+e.g. array1: [1, 3, 5, 10, 20] array2: [2, 4, 5, 10, 20] array3: [2, 4, 10, 20]
+common elements = > 10 & 20 result = > 10
+Constraints:
+* Any number of arrays
+* Each array could be of any size
+* [execution time limit] 4 seconds(js)
+
+10
+10
+10
+"""
+
+
+def smallest_common_num(arrays):
+ idxs = [0] * len(arrays)
+
+ largest_num = float('-inf')
+ largest_arrays_idxs = set()
+
+ while len(largest_arrays_idxs) != len(arrays):
+ for idx, array in enumerate(arrays):
+ if idxs[idx] >= len(array):
+ return None
+
+ if array[idxs[idx]] > largest_num:
+ largest_num = array[idxs[idx]]
+ largest_arrays_idxs = {idx}
+ elif array[idxs[idx]] == largest_num:
+ largest_arrays_idxs.add(idx)
+
+ for idx in range(len(idxs)):
+ if idx not in largest_arrays_idxs:
+ idxs[idx] += 1
+
+ return largest_num
+
+
+print(smallest_common_num([[1, 3, 5, 10, 20],
+ [1, 2, 4, 5, 10, 20],
+ [2, 4, 10, 20]]))