Create hasZeroSumSubArray.py

Author: Amogh Singhal

hasZeroSumSubArray.py

@@ -0,0 +1,38 @@
+# This method returns the sum of numbers
+# present till each index
+
+def getPrefixArray(arr):
+  return [sum(arr[:i]) for i in range(1, len(arr)+1)]
+
+# This method will create a mapping of numbers
+# and the indices they are present at
+
+def getIndexMap(arr):
+  indexMap = {}
+
+  for i in range(len(arr)):
+    if arr[i] not in indexMap.keys():
+      indexMap[arr[i]] = [i,]
+    else:
+      indexMap[arr[i]].append(i)
+  
+  return indexMap
+
+# This method will create the sum prefix of the 
+# current array, if the sum is repeating, then
+# there is a zero sum sub array
+
+def hasZeroSum(arr):
+  prefixArr = getPrefixArray(arr)
+  sumAtIndexMap = getIndexMap(prefixArr)
+
+  for v in sumAtIndexMap.values():
+    if len(v) > 1:
+      return True
+      break
+  return False    
+
+
+ipArray = [1, 4, -2, -2, 5, -4, 3]
+hasZeroSumTrue = hasZeroSum(ipArray)
+print(hasZeroSumTrue)