654 B | 654 chars
import sys
from math import sqrt, pi, sin, factorial
inp = input
# inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = " " : [*map(int,inp().split(x))]
mfi = lambda x = " " : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def f(n, a, b):
A = a + b - n
B = min(a, b)
mx = max(A, B)
mn = min(A, B)
return (mn, mx)
def solve():
flag = ii()
n, a, b, c = mii()
z = f(n, a, b)
l = [*f(n, z[0], c), *f(n, z[1], c)]
if flag == 1:
p(max(min(l), 0))
else:
p(max(max(l), 0))
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()