Buggy python submission (verdict: Runtime Error):
#!/usr/bin/env python3
class SegTree:
    def __init__(self, segfunc, e, v, init_val = None):
        """
        segfunc: function 区間にしたい操作\n
        e: Any 単位元\n
        v: int or List 要素数か格納する配列\n
        init_val: Any 初期値
        """
        self.segfunc = segfunc
        self.e = e
        self.init_val = init_val if init_val != None else e
        if isinstance(v, int):
            v = [self.init_val] * v
        self.n = len(v)
        self.log = (self.n).bit_length()
        self.size = 1 << self.log
        self.tree = [e] * 2 * self.size
        # 1-indexedなのでtree[1:self.size]がN-1要素
        # tree[self.size:self.size + N]が配列
        for i in range(self.n):
            self.tree[self.size + i] = v[i]
        for i in range(self.size - 1, 0, -1):
            self._update(i)

    def set(self, k, x) -> None:
        """
        k番目の値をxに更新\n
        k: index(0-indexed)\n
        x: update value
        """
        k += self.size
        self.tree[k] = x
        for i in range(1, self.log + 1):
            self._update(k >> i)

    def get(self, k):
        """
        a[k]を返す\n
        k: index(0-indexed)
        """
        assert 0 <= k < self.size
        return self.tree[k + self.size]

    def query(self, l, r):
        """
        [l, r)のsegfuncしたものを得る\n
        l: index(0-indexed)\n
        r: index(0-indexed)
        """
        res = self.e
        l += self.size
        r += self.size
        while l < r:
            if l & 1:
                res = self.segfunc(res, self.tree[l])
                l += 1
            if r & 1:
                res = self.segfunc(res, self.tree[r - 1])
            l >>= 1
            r >>= 1
        return res

    def all_query(self):
        """
        全範囲にsegfuncしたものを得る
        """
        return self.tree[1]

    # 二分探索実装、いる？

    def _update(self, k):
        self.tree[k] = self.segfunc(self.tree[k * 2], self.tree[k * 2 + 1])

#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

MAX_A = 300005

dp = SegTree(max, 0, 100, 0)
for i in range(N):
    x = A[i]
    now = dp.query(max(0, x - K), min(x + K + 1, MAX_A)) + 1
    dp.set(x, now)

ans = dp.all_query()
print(ans)


Fixed submission:
import types

_atcoder_code = """
# Python port of AtCoder Library.

__version__ = '0.0.1'
"""

atcoder = types.ModuleType('atcoder')
exec(_atcoder_code, atcoder.__dict__)

_atcoder__bit_code = """
def _ceil_pow2(n: int) -> int:
    x = 0
    while (1 << x) < n:
        x += 1

    return x


def _bsf(n: int) -> int:
    x = 0
    while n % 2 == 0:
        x += 1
        n //= 2

    return x
"""

atcoder._bit = types.ModuleType('atcoder._bit')
exec(_atcoder__bit_code, atcoder._bit.__dict__)


_atcoder_segtree_code = """
import typing

# import atcoder._bit


class SegTree:
    def __init__(self,
                 op: typing.Callable[[typing.Any, typing.Any], typing.Any],
                 e: typing.Any,
                 v: typing.Union[int, typing.List[typing.Any]]) -> None:
        self._op = op
        self._e = e

        if isinstance(v, int):
            v = [e] * v

        self._n = len(v)
        self._log = atcoder._bit._ceil_pow2(self._n)
        self._size = 1 << self._log
        self._d = [e] * (2 * self._size)

        for i in range(self._n):
            self._d[self._size + i] = v[i]
        for i in range(self._size - 1, 0, -1):
            self._update(i)

    def set(self, p: int, x: typing.Any) -> None:
        assert 0 <= p < self._n

        p += self._size
        self._d[p] = x
        for i in range(1, self._log + 1):
            self._update(p >> i)

    def get(self, p: int) -> typing.Any:
        assert 0 <= p < self._n

        return self._d[p + self._size]

    def prod(self, left: int, right: int) -> typing.Any:
        assert 0 <= left <= right <= self._n
        sml = self._e
        smr = self._e
        left += self._size
        right += self._size

        while left < right:
            if left & 1:
                sml = self._op(sml, self._d[left])
                left += 1
            if right & 1:
                right -= 1
                smr = self._op(self._d[right], smr)
            left >>= 1
            right >>= 1

        return self._op(sml, smr)

    def all_prod(self) -> typing.Any:
        return self._d[1]

    def max_right(self, left: int,
                  f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= left <= self._n
        assert f(self._e)

        if left == self._n:
            return self._n

        left += self._size
        sm = self._e

        first = True
        while first or (left & -left) != left:
            first = False
            while left % 2 == 0:
                left >>= 1
            if not f(self._op(sm, self._d[left])):
                while left < self._size:
                    left *= 2
                    if f(self._op(sm, self._d[left])):
                        sm = self._op(sm, self._d[left])
                        left += 1
                return left - self._size
            sm = self._op(sm, self._d[left])
            left += 1

        return self._n

    def min_left(self, right: int,
                 f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= right <= self._n
        assert f(self._e)

        if right == 0:
            return 0

        right += self._size
        sm = self._e

        first = True
        while first or (right & -right) != right:
            first = False
            right -= 1
            while right > 1 and right % 2:
                right >>= 1
            if not f(self._op(self._d[right], sm)):
                while right < self._size:
                    right = 2 * right + 1
                    if f(self._op(self._d[right], sm)):
                        sm = self._op(self._d[right], sm)
                        right -= 1
                return right + 1 - self._size
            sm = self._op(self._d[right], sm)

        return 0

    def _update(self, k: int) -> None:
        self._d[k] = self._op(self._d[2 * k], self._d[2 * k + 1])
"""

atcoder.segtree = types.ModuleType('atcoder.segtree')
atcoder.segtree.__dict__['atcoder'] = atcoder
atcoder.segtree.__dict__['atcoder._bit'] = atcoder._bit
exec(_atcoder_segtree_code, atcoder.segtree.__dict__)
SegTree = atcoder.segtree.SegTree

#!/usr/bin/env python3

# from atcoder.segtree import SegTree
#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

op = max
e = 0

dp = SegTree(op, e, 300005)

for i in range(N):
    x = A[i]
    now = dp.prod(max(x - K, 0), min(x + K + 1, 300005)) + 1
    dp.set(x, now)

ans = dp.prod(0, 300005)
print(ans)

Buggy python submission (verdict: Runtime Error):
#!/usr/bin/env python3
class SegTree:
    def __init__(self, segfunc, e, v, init_val = None):
        """
        segfunc: function 区間にしたい操作\n
        e: Any 単位元\n
        v: int or List 要素数か格納する配列\n
        init_val: Any 初期値
        """
        self.segfunc = segfunc
        self.e = e
        self.init_val = init_val if init_val != None else e
        if isinstance(v, int):
            v = [self.init_val] * v
        self.n = len(v)
        self.log = (self.n).bit_length()
        self.size = 1 << self.log
        self.tree = [e] * 2 * self.size
        # 1-indexedなのでtree[1:self.size]がN-1要素
        # tree[self.size:self.size + N]が配列
        self.tree[self.size :self.size + self.n] = v
        for i in range(self.size - 1, 0, -1):
            self._update(i)

    def set(self, k, x) -> None:
        """
        k番目の値をxに更新\n
        k: index(0-indexed)\n
        x: update value
        """
        k += self.size
        self.tree[k] = x

        for i in range(1, self.log + 1):
            self._update(k >> i)

    def get(self, k):
        """
        a[k]を返す\n
        k: index(0-indexed)
        """
        assert 0 <= k < self.size
        return self.tree[k + self.size]

    def query(self, l, r):
        """
        [l, r)のsegfuncしたものを得る\n
        l: index(0-indexed)\n
        r: index(0-indexed)
        """
        res = self.e
        l += self.size
        r += self.size
        while l < r:
            if l & 1:
                res = self.segfunc(res, self.tree[l])
                l += 1
            if r & 1:
                res = self.segfunc(res, self.tree[r - 1])
            l >>= 1
            r >>= 1
        return res

    def all_query(self):
        """
        全範囲にsegfuncしたものを得る
        """
        return self.tree[1]

    # 二分探索実装、いる？

    def _update(self, k):
        self.tree[k] = self.segfunc(self.tree[k * 2], self.tree[k * 2 + 1])

#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

MAX_A = 300005

dp = SegTree(max, 0, 100, 0)
for i in range(N):
    x = A[i]
    now = dp.query(max(0, x - K), min(x + K + 1, MAX_A)) + 1
    dp.set(x, now)

ans = dp.all_query()
print(ans)


Fixed submission:
import types

_atcoder_code = """
# Python port of AtCoder Library.

__version__ = '0.0.1'
"""

atcoder = types.ModuleType('atcoder')
exec(_atcoder_code, atcoder.__dict__)

_atcoder__bit_code = """
def _ceil_pow2(n: int) -> int:
    x = 0
    while (1 << x) < n:
        x += 1

    return x


def _bsf(n: int) -> int:
    x = 0
    while n % 2 == 0:
        x += 1
        n //= 2

    return x
"""

atcoder._bit = types.ModuleType('atcoder._bit')
exec(_atcoder__bit_code, atcoder._bit.__dict__)


_atcoder_segtree_code = """
import typing

# import atcoder._bit


class SegTree:
    def __init__(self,
                 op: typing.Callable[[typing.Any, typing.Any], typing.Any],
                 e: typing.Any,
                 v: typing.Union[int, typing.List[typing.Any]]) -> None:
        self._op = op
        self._e = e

        if isinstance(v, int):
            v = [e] * v

        self._n = len(v)
        self._log = atcoder._bit._ceil_pow2(self._n)
        self._size = 1 << self._log
        self._d = [e] * (2 * self._size)

        for i in range(self._n):
            self._d[self._size + i] = v[i]
        for i in range(self._size - 1, 0, -1):
            self._update(i)

    def set(self, p: int, x: typing.Any) -> None:
        assert 0 <= p < self._n

        p += self._size
        self._d[p] = x
        for i in range(1, self._log + 1):
            self._update(p >> i)

    def get(self, p: int) -> typing.Any:
        assert 0 <= p < self._n

        return self._d[p + self._size]

    def prod(self, left: int, right: int) -> typing.Any:
        assert 0 <= left <= right <= self._n
        sml = self._e
        smr = self._e
        left += self._size
        right += self._size

        while left < right:
            if left & 1:
                sml = self._op(sml, self._d[left])
                left += 1
            if right & 1:
                right -= 1
                smr = self._op(self._d[right], smr)
            left >>= 1
            right >>= 1

        return self._op(sml, smr)

    def all_prod(self) -> typing.Any:
        return self._d[1]

    def max_right(self, left: int,
                  f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= left <= self._n
        assert f(self._e)

        if left == self._n:
            return self._n

        left += self._size
        sm = self._e

        first = True
        while first or (left & -left) != left:
            first = False
            while left % 2 == 0:
                left >>= 1
            if not f(self._op(sm, self._d[left])):
                while left < self._size:
                    left *= 2
                    if f(self._op(sm, self._d[left])):
                        sm = self._op(sm, self._d[left])
                        left += 1
                return left - self._size
            sm = self._op(sm, self._d[left])
            left += 1

        return self._n

    def min_left(self, right: int,
                 f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= right <= self._n
        assert f(self._e)

        if right == 0:
            return 0

        right += self._size
        sm = self._e

        first = True
        while first or (right & -right) != right:
            first = False
            right -= 1
            while right > 1 and right % 2:
                right >>= 1
            if not f(self._op(self._d[right], sm)):
                while right < self._size:
                    right = 2 * right + 1
                    if f(self._op(self._d[right], sm)):
                        sm = self._op(self._d[right], sm)
                        right -= 1
                return right + 1 - self._size
            sm = self._op(self._d[right], sm)

        return 0

    def _update(self, k: int) -> None:
        self._d[k] = self._op(self._d[2 * k], self._d[2 * k + 1])
"""

atcoder.segtree = types.ModuleType('atcoder.segtree')
atcoder.segtree.__dict__['atcoder'] = atcoder
atcoder.segtree.__dict__['atcoder._bit'] = atcoder._bit
exec(_atcoder_segtree_code, atcoder.segtree.__dict__)
SegTree = atcoder.segtree.SegTree

#!/usr/bin/env python3

# from atcoder.segtree import SegTree
#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

op = max
e = 0

dp = SegTree(op, e, 300005)

for i in range(N):
    x = A[i]
    now = dp.prod(max(x - K, 0), min(x + K + 1, 300005)) + 1
    dp.set(x, now)

ans = dp.prod(0, 300005)
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import types

_atcoder_code = """
# Python port of AtCoder Library.

__version__ = '0.0.1'
"""

atcoder = types.ModuleType('atcoder')
exec(_atcoder_code, atcoder.__dict__)

_atcoder__bit_code = """
def _ceil_pow2(n: int) -> int:
    x = 0
    while (1 << x) < n:
        x += 1

    return x


def _bsf(n: int) -> int:
    x = 0
    while n % 2 == 0:
        x += 1
        n //= 2

    return x
"""

atcoder._bit = types.ModuleType('atcoder._bit')
exec(_atcoder__bit_code, atcoder._bit.__dict__)


_atcoder_segtree_code = """
import typing

# import atcoder._bit


class SegTree:
    def __init__(self,
                 op: typing.Callable[[typing.Any, typing.Any], typing.Any],
                 e: typing.Any,
                 v: typing.Union[int, typing.List[typing.Any]]) -> None:
        self._op = op
        self._e = e

        if isinstance(v, int):
            v = [e] * v

        self._n = len(v)
        self._log = atcoder._bit._ceil_pow2(self._n)
        self._size = 1 << self._log
        self._d = [e] * (2 * self._size)

        for i in range(self._n):
            self._d[self._size + i] = v[i]
        for i in range(self._size - 1, 0, -1):
            self._update(i)

    def set(self, p: int, x: typing.Any) -> None:
        assert 0 <= p < self._n

        p += self._size
        self._d[p] = x
        for i in range(1, self._log + 1):
            self._update(p >> i)

    def get(self, p: int) -> typing.Any:
        assert 0 <= p < self._n

        return self._d[p + self._size]

    def prod(self, left: int, right: int) -> typing.Any:
        assert 0 <= left <= right <= self._n
        sml = self._e
        smr = self._e
        left += self._size
        right += self._size

        while left < right:
            if left & 1:
                sml = self._op(sml, self._d[left])
                left += 1
            if right & 1:
                right -= 1
                smr = self._op(self._d[right], smr)
            left >>= 1
            right >>= 1

        return self._op(sml, smr)

    def all_prod(self) -> typing.Any:
        return self._d[1]

    def max_right(self, left: int,
                  f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= left <= self._n
        assert f(self._e)

        if left == self._n:
            return self._n

        left += self._size
        sm = self._e

        first = True
        while first or (left & -left) != left:
            first = False
            while left % 2 == 0:
                left >>= 1
            if not f(self._op(sm, self._d[left])):
                while left < self._size:
                    left *= 2
                    if f(self._op(sm, self._d[left])):
                        sm = self._op(sm, self._d[left])
                        left += 1
                return left - self._size
            sm = self._op(sm, self._d[left])
            left += 1

        return self._n

    def min_left(self, right: int,
                 f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= right <= self._n
        assert f(self._e)

        if right == 0:
            return 0

        right += self._size
        sm = self._e

        first = True
        while first or (right & -right) != right:
            first = False
            right -= 1
            while right > 1 and right % 2:
                right >>= 1
            if not f(self._op(self._d[right], sm)):
                while right < self._size:
                    right = 2 * right + 1
                    if f(self._op(self._d[right], sm)):
                        sm = self._op(self._d[right], sm)
                        right -= 1
                return right + 1 - self._size
            sm = self._op(self._d[right], sm)

        return 0

    def _update(self, k: int) -> None:
        self._d[k] = self._op(self._d[2 * k], self._d[2 * k + 1])
"""

atcoder.segtree = types.ModuleType('atcoder.segtree')
atcoder.segtree.__dict__['atcoder'] = atcoder
atcoder.segtree.__dict__['atcoder._bit'] = atcoder._bit
exec(_atcoder_segtree_code, atcoder.segtree.__dict__)
SegTree = atcoder.segtree.SegTree

#!/usr/bin/env python3

# from atcoder.segtree import SegTree
#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

op = max
e = 0

dp = SegTree(op, e, 300005)

for i in range(N):
    x = A[i]
    now = dp.prod(max(x - K, 0), min(x + K + 1, 300005)) + 1
    dp.set(x, now)

ans = dp.prod(0, 300005)
print(ans)


Fixed submission:
import types

_atcoder_code = """
# Python port of AtCoder Library.

__version__ = '0.0.1'
"""

atcoder = types.ModuleType('atcoder')
exec(_atcoder_code, atcoder.__dict__)

_atcoder__bit_code = """
def _ceil_pow2(n: int) -> int:
    x = 0
    while (1 << x) < n:
        x += 1

    return x


def _bsf(n: int) -> int:
    x = 0
    while n % 2 == 0:
        x += 1
        n //= 2

    return x
"""

atcoder._bit = types.ModuleType('atcoder._bit')
exec(_atcoder__bit_code, atcoder._bit.__dict__)


_atcoder_segtree_code = """
import typing

# import atcoder._bit


class SegTree:
    def __init__(self,
                 op: typing.Callable[[typing.Any, typing.Any], typing.Any],
                 e: typing.Any,
                 v: typing.Union[int, typing.List[typing.Any]]) -> None:
        self._op = op
        self._e = e

        if isinstance(v, int):
            v = [e] * v

        self._n = len(v)
        self._log = atcoder._bit._ceil_pow2(self._n)
        self._size = 1 << self._log
        self._d = [e] * (2 * self._size)

        for i in range(self._n):
            self._d[self._size + i] = v[i]
        for i in range(self._size - 1, 0, -1):
            self._update(i)

    def set(self, p: int, x: typing.Any) -> None:
        assert 0 <= p < self._n

        p += self._size
        self._d[p] = x
        for i in range(1, self._log + 1):
            self._update(p >> i)

    def get(self, p: int) -> typing.Any:
        assert 0 <= p < self._n

        return self._d[p + self._size]

    def prod(self, left: int, right: int) -> typing.Any:
        assert 0 <= left <= right <= self._n
        sml = self._e
        smr = self._e
        left += self._size
        right += self._size

        while left < right:
            if left & 1:
                sml = self._op(sml, self._d[left])
                left += 1
            if right & 1:
                right -= 1
                smr = self._op(self._d[right], smr)
            left >>= 1
            right >>= 1

        return self._op(sml, smr)

    def all_prod(self) -> typing.Any:
        return self._d[1]

    def max_right(self, left: int,
                  f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= left <= self._n
        assert f(self._e)

        if left == self._n:
            return self._n

        left += self._size
        sm = self._e

        first = True
        while first or (left & -left) != left:
            first = False
            while left % 2 == 0:
                left >>= 1
            if not f(self._op(sm, self._d[left])):
                while left < self._size:
                    left *= 2
                    if f(self._op(sm, self._d[left])):
                        sm = self._op(sm, self._d[left])
                        left += 1
                return left - self._size
            sm = self._op(sm, self._d[left])
            left += 1

        return self._n

    def min_left(self, right: int,
                 f: typing.Callable[[typing.Any], bool]) -> int:
        assert 0 <= right <= self._n
        assert f(self._e)

        if right == 0:
            return 0

        right += self._size
        sm = self._e

        first = True
        while first or (right & -right) != right:
            first = False
            right -= 1
            while right > 1 and right % 2:
                right >>= 1
            if not f(self._op(self._d[right], sm)):
                while right < self._size:
                    right = 2 * right + 1
                    if f(self._op(self._d[right], sm)):
                        sm = self._op(self._d[right], sm)
                        right -= 1
                return right + 1 - self._size
            sm = self._op(self._d[right], sm)

        return 0

    def _update(self, k: int) -> None:
        self._d[k] = self._op(self._d[2 * k], self._d[2 * k + 1])
"""

atcoder.segtree = types.ModuleType('atcoder.segtree')
atcoder.segtree.__dict__['atcoder'] = atcoder
atcoder.segtree.__dict__['atcoder._bit'] = atcoder._bit
exec(_atcoder_segtree_code, atcoder.segtree.__dict__)
SegTree = atcoder.segtree.SegTree

#!/usr/bin/env python3

# from atcoder.segtree import SegTree
#import
#import math
#import numpy as np
#= int(input())
#= input()
N, K = map(int, input().split())
A = [int(input()) for _ in range(N)]

op = max
e = 0

dp = SegTree(op, e, 300005)

for i in range(N):
    x = A[i]
    now = dp.prod(max(x - K, 0), min(x + K + 1, 300005)) + 1
    dp.set(x, now)

ans = dp.prod(0, 300005)
print(ans)