#!/usr/bin/python
from itertools import izip, islice
each_cons = lambda xs, n: izip(*(islice(xs, i, None) for i in xrange(n)))

def valid(a, b, c):
    if len(set((a, b, c))) != 3:
        return 0
    _, y, _ = sorted((a, b, c))
    return y == a or y == c

n = int(raw_input())
As = map(int, raw_input().split())
print len(filter(lambda x: valid(*x), each_cons(As, 3)))