def main():
    N, Y = [int(i) for i in input().split()]

    A = []
    B = []

    for i in range(N):
        a, b = [int(i) for i in input().split()]
        A.append(a)
        B.append(b)

    B.sort()
    B.reverse()
    A.sort()
    A.reverse()

    cnt = 0
    for i in range(1000000):
        if Y <= 0:
            print(cnt)
            return

        b_m = max(B, default=0)
        a_m = max(A)
        if b_m > a_m:
            Y = Y - b_m
            B.remove(b_m)
            cnt += 1
        else:
            if Y % a_m == 0:
                c = Y / a_m
                print(cnt + c)
                return
            else:
                c = Y / a_m
                print(cnt + 1)
                return


main()
