w, m, n = map(int,input().split())
#把数组弄出来
a = []
for i in range(10000 // w + 10):
    b = []
    for j in range(1 + w * i, w * (i + 1) + 1):
        b.append(j)
    if i % 2 != 0:
        b = b[::-1]
    a.append(b)
#规定m为大数
if m < n:
    m, n = n, m
#确定m和n所在的行
mp = (m - 1) // w
np = (n - 1) // w
#确定大数所在的列，因为小数不动，所以不考虑小数
fm = 0
for i in range(w):
    if a[mp][i] == m:
        fm = i
#res1记录移动到同一行所需的次数
res1 = 0
t = True
while t:
    if mp == np:
        break
    mp -= 1
    res1 += 1
#res2记录同一行内所需的步数
res2 = abs(a[mp][fm] - n)
res = res1 + res2
print(res)