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Program to find maximum number of non-overlapping subarrays with sum equals target using Python

Suppose we have an array nums and another value called target. Now we have to find the maximum number of non-empty non-overlapping subarrays such that the sum of values in each different subarray is same as target.

So, if the input is like nums = [3,2,4,5,2,1,5] target = 6, then the output will be 2 as there are two subarrays [2,4] and [1,5] whose sum is same as 6.

To solve this, we will follow these steps −

  • t := a new set with single element 0

  • temp := 0

  • ans:= 0

  • for each i in nums, do

    • temp := temp + i

    • prev := temp - target

    • if prev is in t, then

      • ans := ans + 1

      • t := a new set with single element temp

    • otherwise,

      • insert temp into t

  • return ans

Let us see the following implementation to get better understanding −

Example

def solve(nums, target):
   t = set([0])
   temp = 0
   ans=0
   for i in nums:
      temp += i
      prev = temp-target
      if prev in t:
         ans += 1
         t = set([temp])
      else:
         t.add(temp)
   return ans
nums = [3,2,4,5,2,1,5]
target = 6
print(solve(nums, target))

Input

"poput","vwput",9

Output

2