import sys

sys.setrecursionlimit(10**7)
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 LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


N,L = MI()
L *= 60
S = LS()

songs = [0]  # 1-index
for s in S:
    m,s = map(int,s.split(':'))
    songs.append(60*m+s)

if sum(songs) <= L:
    print(N)
    exit()

dp = [[[0]*L for _ in range(N+1)] for _ in range(N+1)]
# dp[i][j][k] = 1~i曲目からj曲選んで、合計再生時間k分となる組み合わせ
dp[0][0][0] = 1
for i in range(1,N+1):
    s = songs[i]
    for j in range(i+1):
        for k in range(L):
            if j >= 1 and k >= s:
                dp[i][j][k] = dp[i-1][j][k]+dp[i-1][j-1][k-s]
            else:
                dp[i][j][k] = dp[i-1][j][k]

fac = [1]
for i in range(1,N+1):
    fac.append(fac[-1]*i)

ans = 0
for i in range(1,N+1):
    dp2 = [[0]*L for _ in range(N+1)]
    # dp2[j][k] = i曲目以外のj曲選んで、合計再生時間k分となる組み合わせ
    s = songs[i]
    for j in range(N+1):
        coefficient = fac[j]*fac[N-j-1]/fac[N]
        for k in range(L):
            if j >= 1 and k >= s:
                dp2[j][k] = dp[-1][j][k]-dp2[j-1][k-s]
            else:
                dp2[j][k] = dp[-1][j][k]

            ans += dp2[j][k]*coefficient

print(ans)