
# 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

if sys.argv[-1] == 'ONLINE_JUDGE':

    import os

    import re

    with open(__file__) as f:

        source = f.read().split('###''nbacl')

    for s in source[1:]:

        s = re.sub("'''.*", '', s)

        sp = s.split(maxsplit=1)

        if os.path.dirname(sp[0]):

            os.makedirs(os.path.dirname(sp[0]), exist_ok=True)

        with open(sp[0], 'w') as f:

            f.write(sp[1])

    from nbmodule import cc

    cc.compile()

import numpy as np

from numpy import int64

from nbmodule import solve





f = open(0)

N, K = [int(x) for x in f.readline().split()]

A = np.fromstring(f.read(), dtype=int64, sep=' ')

ans = solve(N, K, A)

print(ans)



'''

###nbacl nbmodule.py

import numpy as np

from numpy import int64

from numba import njit

from numba.types import i8

from numba.pycc import CC

import nbacl.segtree as seg

cc = CC('my_module')





@cc.export('solve', (i8, i8, i8[:]))

@njit

def solve(N, K, A):

    dp = np.zeros(300_001, dtype=int64)

    d = seg.segtree(dp, max, 0)

    for i in range(N):

        x = seg.prod(d, max, (A[i] - K) if A[i] > K else 0, (A[i] + K + 1) if A[i] + K < 300_000 else 300_001) + 1

        seg.set(d, max, A[i], x)

    return seg.all_prod(d)





if __name__ == '__main__':

    cc.compile()

###nbacl nbacl/segtree.py

import numpy as np

from numba import njit

from numba.types import i8





@njit

def ceil_pow2(n):

    x = 0

    while (1 << x) < n:

        x += 1

    return x





@njit

def segtree(a, op, e):

    log = ceil_pow2(a.shape[0])

    size = 1 << log

    d = np.empty(size * 2, dtype=a.dtype)

    d[size:size + len(a)] = a

    d[size + len(a):] = e

    # e

    d[0] = e

    for i in range(size - 1, 0, -1):

        update(d, i, op)

    return d





@njit

def update(d, k, op):

    d[k] = op(d[2 * k], d[2 * k + 1])





@njit

def set(d, op, p, x):

    p += d.shape[0] // 2

    d[p] = x

    while p > 1:

        p >>= 1

        update(d, p, op)





@njit

def get(d, p):

    return d[p + d.shape[0] // 2]





@njit

def prod(d, op, left, right):

    size = d.shape[0] // 2

    sml = d[0]

    smr = d[0]

    left += size

    right += size



    while left < right:

        if left & 1:

            sml = op(sml, d[left])

            left += 1

        if right & 1:

            right -= 1

            smr = op(d[right], smr)

        left >>= 1

        right >>= 1



    return op(sml, smr)





@njit

def all_prod(d):

    return d[1]



'''


# optimized version of the same code:

import sys

if sys.argv[-1] == 'ONLINE_JUDGE':

    import os

    import re

    with open(__file__) as f:

        source = f.read().split('###''nbacl')

    for s in source[1:]:

        s = re.sub("'''.*", '', s)

        sp = s.split(maxsplit=1)

        if os.path.dirname(sp[0]):

            os.makedirs(os.path.dirname(sp[0]), exist_ok=True)

        with open(sp[0], 'w') as f:

            f.write(sp[1])

    from nbmodule import cc

    cc.compile()

import numpy as np

from numpy import int64

from nbmodule import solve





f = open(0)

N, K = [int(x) for x in f.readline().split()]

A = np.fromstring(f.read(), dtype=int64, sep=' ')

ans = solve(N, K, A)

print(ans)



'''

###nbacl nbmodule.py

import numpy as np

from numpy import int64

from numba import njit

from numba.types import i8

from numba.pycc import CC

import nbacl.segtree as seg

cc = CC('nbmodule')





@cc.export('solve', (i8, i8, i8[:]))

@njit

def solve(N, K, A):

    dp = np.zeros(300_001, dtype=int64)

    d = seg.segtree(dp, max, 0)

    for i in range(N):

        x = seg.prod(d, max, (A[i] - K) if A[i] > K else 0, (A[i] + K + 1) if A[i] + K < 300_000 else 300_001) + 1

        seg.set(d, max, A[i], x)

    return seg.all_prod(d)





if __name__ == '__main__':

    cc.compile()

###nbacl nbacl/segtree.py

import numpy as np

from numba import njit

from numba.types import i8





@njit

def ceil_pow2(n):

    x = 0

    while (1 << x) < n:

        x += 1

    return x





@njit

def segtree(a, op, e):

    log = ceil_pow2(a.shape[0])

    size = 1 << log

    d = np.empty(size * 2, dtype=a.dtype)

    d[size:size + len(a)] = a

    d[size + len(a):] = e

    # e

    d[0] = e

    for i in range(size - 1, 0, -1):

        update(d, i, op)

    return d





@njit

def update(d, k, op):

    d[k] = op(d[2 * k], d[2 * k + 1])





@njit

def set(d, op, p, x):

    p += d.shape[0] // 2

    d[p] = x

    while p > 1:

        p >>= 1

        update(d, p, op)





@njit

def get(d, p):

    return d[p + d.shape[0] // 2]





@njit

def prod(d, op, left, right):

    size = d.shape[0] // 2

    sml = d[0]

    smr = d[0]

    left += size

    right += size



    while left < right:

        if left & 1:

            sml = op(sml, d[left])

            left += 1

        if right & 1:

            right -= 1

            smr = op(d[right], smr)

        left >>= 1

        right >>= 1



    return op(sml, smr)





@njit

def all_prod(d):

    return d[1]



'''

import sys

if sys.argv[-1] == "ONLINE_JUDGE":
    import os
    import re

    with open(__file__) as f:
        source = f.read().split("###" "nbacl")
    for s in source[1:]:
        s = re.sub("'''.*", "", s)
        sp = s.split(maxsplit=1)
        if os.path.dirname(sp[0]):
            os.makedirs(os.path.dirname(sp[0]), exist_ok=True)
        with open(sp[0], "w") as f:
            f.write(sp[1])
    from nbmodule import cc

    cc.compile()
import numpy as np
from numpy import int64
from nbmodule import solve

f = open(0)
N, K = [int(x) for x in f.readline().split()]
A = np.fromstring(f.read(), dtype=int64, sep=" ")
ans = solve(N, K, A)
print(ans)
"""
###nbacl nbmodule.py
import numpy as np
from numpy import int64
from numba import njit
from numba.types import i8
from numba.pycc import CC
import nbacl.segtree as seg
cc = CC('my_module')
@cc.export('solve', (i8, i8, i8[:]))
@njit
def solve(N, K, A):
    dp = np.zeros(300_001, dtype=int64)
    d = seg.segtree(dp, max, 0)
    for i in range(N):
        x = seg.prod(d, max, (A[i] - K) if A[i] > K else 0, (A[i] + K + 1) if A[i] + K < 300_000 else 300_001) + 1
        seg.set(d, max, A[i], x)
    return seg.all_prod(d)
if __name__ == '__main__':
    cc.compile()
###nbacl nbacl/segtree.py
import numpy as np
from numba import njit
from numba.types import i8
@njit
def ceil_pow2(n):
    x = 0
    while (1 << x) < n:
        x += 1
    return x
@njit
def segtree(a, op, e):
    log = ceil_pow2(a.shape[0])
    size = 1 << log
    d = np.empty(size * 2, dtype=a.dtype)
    d[size:size + len(a)] = a
    d[size + len(a):] = e
    # e
    d[0] = e
    for i in range(size - 1, 0, -1):
        update(d, i, op)
    return d
@njit
def update(d, k, op):
    d[k] = op(d[2 * k], d[2 * k + 1])
@njit
def set(d, op, p, x):
    p += d.shape[0] // 2
    d[p] = x
    while p > 1:
        p >>= 1
        update(d, p, op)
@njit
def get(d, p):
    return d[p + d.shape[0] // 2]
@njit
def prod(d, op, left, right):
    size = d.shape[0] // 2
    sml = d[0]
    smr = d[0]
    left += size
    right += size
    while left < right:
        if left & 1:
            sml = op(sml, d[left])
            left += 1
        if right & 1:
            right -= 1
            smr = op(d[right], smr)
        left >>= 1
        right >>= 1
    return op(sml, smr)
@njit
def all_prod(d):
    return d[1]
"""

import sys

if sys.argv[-1] == "ONLINE_JUDGE":
    import os
    import re

    with open(__file__) as f:
        source = f.read().split("###" "nbacl")
    for s in source[1:]:
        s = re.sub("'''.*", "", s)
        sp = s.split(maxsplit=1)
        if os.path.dirname(sp[0]):
            os.makedirs(os.path.dirname(sp[0]), exist_ok=True)
        with open(sp[0], "w") as f:
            f.write(sp[1])
    from nbmodule import cc

    cc.compile()
import numpy as np
from numpy import int64
from nbmodule import solve

f = open(0)
N, K = [int(x) for x in f.readline().split()]
A = np.fromstring(f.read(), dtype=int64, sep=" ")
ans = solve(N, K, A)
print(ans)
"""
###nbacl nbmodule.py
import numpy as np
from numpy import int64
from numba import njit
from numba.types import i8
from numba.pycc import CC
import nbacl.segtree as seg
cc = CC('nbmodule')
@cc.export('solve', (i8, i8, i8[:]))
@njit
def solve(N, K, A):
    dp = np.zeros(300_001, dtype=int64)
    d = seg.segtree(dp, max, 0)
    for i in range(N):
        x = seg.prod(d, max, (A[i] - K) if A[i] > K else 0, (A[i] + K + 1) if A[i] + K < 300_000 else 300_001) + 1
        seg.set(d, max, A[i], x)
    return seg.all_prod(d)
if __name__ == '__main__':
    cc.compile()
###nbacl nbacl/segtree.py
import numpy as np
from numba import njit
from numba.types import i8
@njit
def ceil_pow2(n):
    x = 0
    while (1 << x) < n:
        x += 1
    return x
@njit
def segtree(a, op, e):
    log = ceil_pow2(a.shape[0])
    size = 1 << log
    d = np.empty(size * 2, dtype=a.dtype)
    d[size:size + len(a)] = a
    d[size + len(a):] = e
    # e
    d[0] = e
    for i in range(size - 1, 0, -1):
        update(d, i, op)
    return d
@njit
def update(d, k, op):
    d[k] = op(d[2 * k], d[2 * k + 1])
@njit
def set(d, op, p, x):
    p += d.shape[0] // 2
    d[p] = x
    while p > 1:
        p >>= 1
        update(d, p, op)
@njit
def get(d, p):
    return d[p + d.shape[0] // 2]
@njit
def prod(d, op, left, right):
    size = d.shape[0] // 2
    sml = d[0]
    smr = d[0]
    left += size
    right += size
    while left < right:
        if left & 1:
            sml = op(sml, d[left])
            left += 1
        if right & 1:
            right -= 1
            smr = op(d[right], smr)
        left >>= 1
        right >>= 1
    return op(sml, smr)
@njit
def all_prod(d):
    return d[1]
"""

-cc = CC('my_module') +cc = CC('nbmodule')