import math
import sys
def S(): return sys.stdin.readline().rstrip()
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int, sys.stdin.readline().rstrip().split())
def LI(): return list(map(int, sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())

n = I()
m = I()

for _ in range(m):
    p, q = MI()
    if n == p:
        n = q
    elif n == q:
        n = p
    else:
        continue
print(n)