import sys
L = [int(l[:-1]) for l in sys.stdin.readlines()]
print(sum([0,1][a<d] for (a,d) in zip(L, L[3:])))

# window1 = [A,B,C] ; window2 = [B,C,D]
# sum(Window1) <? sum(window2)
# (A+B+C) <? (B+C+D)
# (A+B+C)-B-C <? (B+C+D)-B-C
# A <? D
# eg: comparing A+B+C and B+C+D is the same as comparing A and D