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import sys

n = int(sys.stdin.readline().strip())
X = [int(x) for x in sys.stdin.readline().split(" ")]

WU = [0] * n
WC = [1] * n
NU = [0] * n
NC = [1] * n

if __name__ == "__main__":

	for i in range(1, n):

		WU[i] = NC[i-1]
		if X[i] > X[i-1]:
			WU[i] = min(WU[i], NU[i-1])

		NU[i] = WC[i-1]
		if X[i] < X[i-1]:
			NU[i] = min(NU[i], WU[i-1])

		WC[i] = min(NU[i-1] + 1, NC[i-1] + 1)
		NC[i] = min(WU[i-1] + 1, WC[i-1] + 1)

	print(min(WU[n-1], NU[n-1], WC[n-1], NC[n-1]))