w, a, b = map(int, input().split())
def check(m, width):
# 将m-1可以避免w的倍数的特殊情况
row = (m - 1) // width + 1
if row % 2 == 1:
col = (m - 1) % width + 1
else:
col = width - (m - 1) % width
return row, col
a_row, a_col = check(a, w)
b_row, b_col = check(b, w)
ans = abs(a_row - b_row) + abs(a_col - b_col)
print(ans)