#!/usr/bin/env python3

def calculate(wind):
    end = wind[-2:]
    if wind[-2:] not in "NESWN": end = end[::-1]
    low = "NESWN".index(end) * 90
    high = low + 90
    curr = low + 45
    for c in wind[-3::-1]:
        if end.index(c) == 0:
            high = curr
        else:
            low = curr
        curr = (low + high) / 2
    return curr


X, Y = sorted("NESW".index(d[0]) * 90 if len(d) == 1 else calculate(d) for d in input().split())
print(min(Y - X, 360 + X - Y))