def SCC_Tarjan(g):
    n = len(g)
    order = [-1]*n # 負なら未処理、[0,n) ならpre-order, n ならvisited
    low = [0]*n
    ord_now = 0
    parent = [-1]*n
    gp = [0]*n
    gp_num = 0
    S = []
    q = []
    for i in range(n):
        if order[i] == -1:
            q.append(i)
            while q:
                v = q.pop()
                if v >= 0:
                    if order[v] != -1: continue
                    order[v] = low[v] = ord_now
                    ord_now += 1
                    S.append(v)
                    q.append(~v)
                    for c in g[v]:
                        if order[c] == -1: 
                            q.append(c)
                            parent[c] = v
                        else:
                            low[v] = min(low[v], order[c])
                else:
                    v = ~v
                    if parent[v] != -1:
                        low[parent[v]] = min(low[parent[v]], low[v])
                    if low[v] == order[v]:
                        while True:
                            w = S.pop()
                            order[w] = n
                            gp[w] = gp_num
                            if w==v: break
                        gp_num += 1
 
    return gp

class TwoSAT:
    def __init__(self, n):
        self._n = n
        self._answer = [False]*n
        self._g = [[] for _ in range(2*n)]

    def add_clause(self, i: int, f: bool, j: int, g: bool) -> None:
        self._g[2*i+1-f].append(2*j+g)
        self._g[2*j+1-g].append(2*i+f)

    def satisfiable(self) -> bool:
        scc_id = SCC_Tarjan(self._g)
        for i in range(self._n):
            if scc_id[2*i] == scc_id[2*i+1]:
                return False
            self._answer[i] = scc_id[2*i] < scc_id[2*i+1]
        return True

    def answer(self):
        return self._answer



n,m = map(int,input().split())
lr = [list(map(int,input().split())) for _ in range(n)]
g = TwoSAT(n)
for i in range(n):
    li,ri = lr[i]
    lli,rri = m-1-ri,m-1-li
    for j in range(i+1,n):
        lj,rj = lr[j]
        if li <= rj and lj <= ri:
            g.add_clause(i,1,j,1)
            g.add_clause(i,0,j,0)
        if lli <= rj and lj <= rri:
            g.add_clause(i,1,j,0)
            g.add_clause(i,0,j,1)

print("YES" if g.satisfiable() else "NO")