###Given an array of non-negative integers, you are initially positioned at the first index of the array.

###Each element in the array represents your maximum jump length at that position.

###Determine if you are able to reach the last index.

###For example:
###A = [2,3,1,1,4], return true.

###A = [3,2,1,0,4], return false.

#time O(n)
#space O(1)
def JumpGame(A):
	step = A[0]
	for i in range(1,len(A)):
		if step > 0:
			step -= 1
			step = max(step,A[i])
		else:
			return False
	return True
