Buggy python submission (verdict: Runtime Error):
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(N+4),segfunc,ide_ele)
for i in range(N):
    a=int(input())
    seg.update(a,seg.query(max(0,a-K),min(N,a+K+1))+1)
print(seg.query(0,N+3))


Fixed submission:
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
b=[int(input()) for _ in range(N)]
c=max(b)
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(c+6),segfunc,ide_ele)
for i in range(N):
    a=b[i]
    seg.update(a,seg.query(max(0,a-K),min(c+2,a+K+1))+1)
print(seg.query(0,c+3))

Buggy python submission (verdict: Runtime Error):
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        # 配列の値を葉にセット
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        # 構築していく
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(N+4),segfunc,ide_ele)
for i in range(N):
    a=int(input())
    seg.update(a,seg.query(max(0,a-K),min(N,a+K+1))+1)
print(seg.query(0,N+3))


Fixed submission:
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
b=[int(input()) for _ in range(N)]
c=max(b)
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(c+6),segfunc,ide_ele)
for i in range(N):
    a=b[i]
    seg.update(a,seg.query(max(0,a-K),min(c+2,a+K+1))+1)
print(seg.query(0,c+3))

Buggy python submission (verdict: Runtime Error):
N,K=map(int,input().split())
class SegTree:
    """
    init(init_val, ide_ele): 配列init_valで初期化 O(N)
    update(k, x): k番目の値をxに更新 O(logN)
    query(l, r): 区間[l, r)をsegfuncしたものを返す O(logN)
    """
    def __init__(self, init_val, segfunc, ide_ele):
        """
        init_val: 配列の初期値
        segfunc: 区間にしたい操作
        ide_ele: 単位元
        n: 要素数
        num: n以上の最小の2のべき乗
        tree: セグメント木(1-index)
        """
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        # 配列の値を葉にセット
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        # 構築していく
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])

    def update(self, k, x):
        """
        k番目の値をxに更新
        k: index(0-index)
        x: update value
        """
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        """
        [l, r)のsegfuncしたものを得る
        l: index(0-index)
        r: index(0-index)
        """
        res = self.ide_ele

        l += self.num
        r += self.num
        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
ide_ele = 0
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(N+1),segfunc,ide_ele)
for i in range(N):
    a=int(input())
    seg.update(a,seg.query(max(0,a-K),min(N,a+K+1))+1)
print(seg.query(0,N+2))


Fixed submission:
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
b=[int(input()) for _ in range(N)]
c=max(b)
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(c+6),segfunc,ide_ele)
for i in range(N):
    a=b[i]
    seg.update(a,seg.query(max(0,a-K),min(c+2,a+K+1))+1)
print(seg.query(0,c+3))

Buggy python submission (verdict: Time Limit Exceeded):
n,k=map(int,input().split())
b=[int(input()) for _ in range(n)]
dp=[0]*(max(b)+1)
c=max(b)
for i in range(n):
    dp[b[i]]=max(dp[b[i]],max(dp[max(0,b[i]-k):min(c+1,b[i]+k+1)])+1)
print(max(dp))


Fixed submission:
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
b=[int(input()) for _ in range(N)]
c=max(b)
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(c+6),segfunc,ide_ele)
for i in range(N):
    a=b[i]
    seg.update(a,seg.query(max(0,a-K),min(c+2,a+K+1))+1)
print(seg.query(0,c+3))

Buggy python submission (verdict: Time Limit Exceeded):
n,k=map(int,input().split())
b=[int(input()) for _ in range(n)]
dp=[[0]*(max(b)+1) for _ in range(n+1)]
a=b[0]
dp[1][a]=1
c=max(b)
for i in range(2,n+1):
    a=b[i-1]
    dp[i][a]=max(dp[i][a],1)
    for j in range(max(a-k,0),min(a+k,c+1)):
        if dp[i-1][j]!=0:
            dp[i][a-(a-j)]=max(dp[i-1][a-(a-j)],dp[i-1][j]+1)
    for j in range(c+1):
        dp[i][j]=max(dp[i][j],dp[i-1][j])
print(max(dp[-1]))


Fixed submission:
N,K=map(int,input().split())
class SegTree:
    def __init__(self, init_val, segfunc, ide_ele):
        n = len(init_val)
        self.segfunc = segfunc
        self.ide_ele = ide_ele
        self.num = 1 << (n - 1).bit_length()
        self.tree = [ide_ele] * 2 * self.num
        for i in range(n):
            self.tree[self.num + i] = init_val[i]
        for i in range(self.num - 1, 0, -1):
            self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])
    def update(self, k, x):
        k += self.num
        self.tree[k] = x
        while k > 1:
            self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
            k >>= 1

    def query(self, l, r):
        res = self.ide_ele
        l += self.num
        r += self.num
        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
ide_ele = 0
b=[int(input()) for _ in range(N)]
c=max(b)
def segfunc(x,y):
    return max(x,y)
seg=SegTree([0]*(c+6),segfunc,ide_ele)
for i in range(N):
    a=b[i]
    seg.update(a,seg.query(max(0,a-K),min(c+2,a+K+1))+1)
print(seg.query(0,c+3))