Find the Winner of an Array Game Using Python

Suppose we have an array called arr, this contains unique elements and we also have another value k. Now consider a game where we take first two elements of the array. In each turn, we compare arr[0] with arr[1], and the larger value wins and remains at position 0 and the smaller value moves to the end of the array. This game will end when a value wins’ k consecutive rounds. We have to find the winner from the array.

So, if the input is like arr = [1,5,6,3,4,2], and k = 3, then the output will be 6 because

• round 1, arr = [1,5,6,3,4,2], winner 5, win count for 5 is 1

• round 2, arr = [5,6,3,4,2,1], winner 6, win count for 6 is 1

• round 3, arr = [6,3,4,2,1,5], winner 6, win count for 6 is 2

• round 3, arr = [6,4,2,1,5,3], winner 6, win count for 6 is 3

So winner is 6 as it won three times (k = 3)

To solve this, we will follow these steps −

• l := size of arr

• prev := arr[0]

• count := 0

• for i in range 1 to l - 1, do

  • if prev > arr[i], then

    • count := count + 1

  • otherwise,

    • prev := arr[i]

    • count := 1

  • if count is same as k, then

    • return prev

• return prev

Let us see the following implementation to get better understanding −

Example

 Live Demo

def solve(arr, k):
   l = len(arr)
   prev = arr[0]
   count = 0
   for i in range(1, l):
      if prev > arr[i]:
         count+=1
      else:
         prev = arr[i]
         count = 1
      if count == k:
         return prev
   return prev
arr = [1,5,6,3,4,2]
k = 3
print(solve(arr, k))

Input

[1,5,6,3,4,2], 3

Output

6