def FIND(initial_position, swaps):
    position = initial_position
    for swap in swaps:
        if position in swap:
            position = swap[0] if position == swap[1] else swap[1]
    return position
N = int(input())
M = int(input())
SWAPS = []
for _ in range(M):
    SWAPS.append(tuple(map(int, input().split())))
print(FIND(N, SWAPS))