
# slower version:

s = input()
for i in range(len(s)):
  if i%2 == 0:
    print(s[i], end = '')


# optimized version of the same code:

s = input()
ans = ''
for i in range(len(s)):
  if i % 2 == 0:
    ans += s[i]
print(ans)



# slower version:

import sys

from operator import itemgetter

from heapq import heapify, heappop, heappush

MAX_INT = int(10e15)

MIN_INT = -MAX_INT

mod = 1000000007

sys.setrecursionlimit(1000000)

def IL(): return list(map(int,input().split()))

def SL(): return input().split()

def I(): return int(sys.stdin.readline())

def S(): return eval(input())



N, T = IL()

ab = [IL() for i in range(N)]

ab.sort(key=itemgetter(0))

#print(ab)



dp = [[0]*(T+1+3000+1) for _ in range(N+1)]

ans = 0

for i in range(N):

  for j in range(T+1+3000+1):

    time, deli = ab[i]

    if 0 <= j-time < T:

      dp[i + 1][j] = max(dp[i][j], dp[i][j - time] + deli)

    else:

      dp[i + 1][j] = dp[i][j]

    ans = max(ans, dp[i + 1][j])

print(ans)



#print(dp)


# optimized version of the same code:

import sys

from collections import deque

MAX_INT = int(10e10)

MIN_INT = -MAX_INT

mod = 1000000007

sys.setrecursionlimit(1000000)

def IL(): return list(map(int,input().split()))

def SL(): return input().split()

def I(): return int(sys.stdin.readline())

def S(): return eval(input())



N,T = IL()

ab = [IL() for i in range(N)]

ab.sort()



ans = 0

dp = [[0]*T for i in range(N+1)]

for i in range(1,N+1):

  a,b = ab[i-1]

  for j in range(T):

    if 0 <= j-a < T:

      dp[i][j] = max(dp[i-1][j], dp[i-1][j-a] + b)

    else:

      dp[i][j] = dp[i-1][j]

  else:

    ans = max(ans, dp[i-1][-1] + b)

print(ans)
import sys
from operator import itemgetter
from heapq import heapify, heappop, heappush

MAX_INT = int(10e15)
MIN_INT = -MAX_INT
mod = 1000000007
sys.setrecursionlimit(1000000)


def IL():
    return list(map(int, input().split()))


def SL():
    return input().split()


def I():
    return int(sys.stdin.readline())


def S():
    return eval(input())


N, T = IL()
ab = [IL() for i in range(N)]
ab.sort(key=itemgetter(0))
# print(ab)
dp = [[0] * (T + 1 + 3000 + 1) for _ in range(N + 1)]
ans = 0
for i in range(N):
    for j in range(T + 1 + 3000 + 1):
        time, deli = ab[i]
        if 0 <= j - time < T:
            dp[i + 1][j] = max(dp[i][j], dp[i][j - time] + deli)
        else:
            dp[i + 1][j] = dp[i][j]
        ans = max(ans, dp[i + 1][j])
print(ans)
# print(dp)

import sys
from collections import deque

MAX_INT = int(10e10)
MIN_INT = -MAX_INT
mod = 1000000007
sys.setrecursionlimit(1000000)


def IL():
    return list(map(int, input().split()))


def SL():
    return input().split()


def I():
    return int(sys.stdin.readline())


def S():
    return eval(input())


N, T = IL()
ab = [IL() for i in range(N)]
ab.sort()
ans = 0
dp = [[0] * T for i in range(N + 1)]
for i in range(1, N + 1):
    a, b = ab[i - 1]
    for j in range(T):
        if 0 <= j - a < T:
            dp[i][j] = max(dp[i - 1][j], dp[i - 1][j - a] + b)
        else:
            dp[i][j] = dp[i - 1][j]
    else:
        ans = max(ans, dp[i - 1][-1] + b)
print(ans)

-from operator import itemgetter -from heapq import heapify, heappop, heappush +from collections import deque -MAX_INT = int(10e15) +MAX_INT = int(10e10) -ab.sort(key=itemgetter(0)) -# print(ab) -dp = [[0] * (T + 1 + 3000 + 1) for _ in range(N + 1)] +ab.sort() -for i in range(N): -    for j in range(T + 1 + 3000 + 1): -        time, deli = ab[i] -        if 0 <= j - time < T: -            dp[i + 1][j] = max(dp[i][j], dp[i][j - time] + deli) +dp = [[0] * T for i in range(N + 1)] +for i in range(1, N + 1): +    a, b = ab[i - 1] +    for j in range(T): +        if 0 <= j - a < T: +            dp[i][j] = max(dp[i - 1][j], dp[i - 1][j - a] + b) -            dp[i + 1][j] = dp[i][j] -        ans = max(ans, dp[i + 1][j]) +            dp[i][j] = dp[i - 1][j] +    else: +        ans = max(ans, dp[i - 1][-1] + b) -# print(dp)