numbers in PI

Author: Partho Biswas

algoexpert.io/python/Numbers_In_Pi.py

@@ -0,0 +1,24 @@
+
+
+# O(n^3) time | O(n + m) space
+def  numbersInPi(pi, numbers):
+    numbersTable = {number: True for number in numbers}
+    minSpaces = getMinSpaces(pi, numbersTable, {}, 0)
+    return -1 if minSpaces == float('inf') else minSpaces
+
+
+def getMinSpaces(pi, numbersTable, cache, idx):
+    if idx == len(pi):
+        return -1
+    if idx in cache:
+        return cache[idx]
+    minSpaces = float('inf')
+    for i in range(idx, len(pi)):
+        prefix = pi[idx:i + 1]
+        if prefix in numbersTable:
+            minSpacesInSiffix = getMinSpaces(pi, numbersTable, cache, i + 1)
+            minSpaces = min(minSpaces, minSpacesInSiffix + 1)
+    cache[idx] = minSpaces
+    return cache[idx]
+
+