def inpf() a=gets.chomp.split(" ").map(&:to_f)end

def inps() a=gets.chomp.split(" ")end

def copy(a) Marshal.load(Marshal.dump(a)) end

def kaijo(n,r = 10**9+7)(n < 2)? 1 : (2..n).inject{|memo,u|memo=(memo*u)%r} end

def na(n,d=0) Array.new(n,d)end

def na2(n,m,d=0) Array.new(n){Array.new(m,d)}end

def na3(n,m,l,d=0) Array.new(n){Array.new(m){Array.new(l,d)}}end

def inp() a=gets.chomp.split(" ").map(&:to_i)end

def r_up(a, b) (a+b-1)/b end

def sum(a) a.inject(:+) end

n,t = inp
tt=[]
a = []
b = []
n.times do |i|
  tt[i] = inp
end
tt.sort_by!{|u|u[0]}
n.times do |i|
  a[i],b[i] = tt[i]
end
ans = 0
dp = na(t+1)
n.times do |i|
  ans = [ans,dp[-2]+b[i]].max
  (0...(dp.size)).reverse_each do |j|
    dp[j] = [dp[j],dp[j-a[i]]+b[i]].max if(j-a[i] >= 0 and j-a[i] < dp.size)
  end
end
p ans