n, m, s = map(int, input().split())

zajete = []
for i in range(m):
    l, r = map(int, input().split())
    for j in range(l, r+1):
        zajete.append(j)

numery = []
for i in range(n):
    if i+1 not in zajete:
        numery.append(i+1)

print(min(numery, key=lambda x: (abs(x-s),x)))