#!/usr/bin/env python3

lines = (x.strip() for x in open("input.txt"))

blacks = set()

for line in lines:
    x, y = 0, 0
    while len(line):
        if line[0] == "n":
            y += 1
            x += 1 if line[1] == "e" else 0
            line = line[2:]
        elif line[0] == "s":
            y -= 1
            x -= 1 if line[1] == "w" else 0
            line = line[2:]
        else:
            x += 1 if line[0] == "e" else -1
            line = line[1:]
    if (x, y) in blacks:
        blacks.discard((x, y))
    else:
        blacks.add((x, y))

print(len(blacks))