Array | Find Transition Point | GeekForGeeks

You are given a sorted array containing only numbers 0 and 1. Find the transition point efficiently. The transition point is a point where "0" ends and "1" begins (0 based indexing). 

Note that, if there is no "1" exists, print -1. 

Note that, in case of all 1s print 0

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def transitionPoint(arr, n):

    count = 1

    

    if(arr.count(1)==n):

        return 0

    elif(arr.count(0)==n):

        return -1

    else:

        for i in range(n-1):

            if(arr[i+1]==1):

                return count

            count +=1

t=int(input())

for i in range(t):

  n=int(input())

  arr=list(map(int,input().strip().split()))  

  print(transitionPoint(arr, n))