#yuki951

n,k=map(int,raw_input().split())
pd=[]
for i in range(n):
 p,d=map(int,raw_input().split())
 pd.append([p,d])
pd.sort(key=lambda x:x[0],reverse=True)
dp=[[-(1<<26)] *2 for i in range(k+1)]
dp[0][0]=0
for p,d in pd:
 for i in range(k,-1,-1):
  dp[i][0]=max(dp[i][0],dp[i][1]+d)
  if i>=p:
   dp[i][1]=max(dp[i][1],dp[i-p][0]+d)
print max([max(i) for i in dp])