Problem p02728 (python)

Fixed submission:
MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 * 2 + 1):
    inv.append(MOD - MOD // i * inv[MOD % i] % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 * 2 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])

stack = [(-1, nodes[0])]
for i in range(N):
    fro, node = stack[i]
    for neigh in node.neighs:
        if neigh.ind == fro:
            continue
        stack.append((node.ind, neigh))

for i in range(N - 1, -1, -1):
    fro, node = stack[i]
    node.val = node.val * fact[node.ndesc - 1] % MOD
    if fro == -1:
        continue
    nodes[fro].ndesc += node.ndesc
    nodes[fro].val = nodes[fro].val * node.val * ifact[node.ndesc] % MOD

stack = [(-1, node, nodes[0].val * inv[N] % MOD)]
for i in range(N):
    fro, node, val = stack[i]
    node.val = val * node.ndesc * inv[max(1, N - node.ndesc)] % MOD
    for neigh in node.neighs:
        if neigh.ind == fro:
            continue
        stack.append((node.ind, neigh, node.val))

for i in range(N):
    print(nodes[i].val)

Buggy submission (verdict: Runtime Error):
import sys

sys.setrecursionlimit(10 ** 5 + 10)

MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 + 1):
    inv.append(MOD - MOD // i * inv[MOD % i] % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])

stack = [(-1, nodes[0])]
for i in range(N):
    fro, node = stack[i]
    for neigh in node.neighs:
        if neigh.ind == fro:
            continue
        stack.append((node.ind, neigh))

for i in range(N - 1, -1, -1):
    fro, node = stack[i]
    node.val = node.val * fact[node.ndesc - 1] % MOD
    if fro == -1:
        continue
    nodes[fro].ndesc += node.ndesc
    nodes[fro].val = nodes[fro].val * node.val * ifact[node.ndesc] % MOD

stack = [(-1, node, nodes[0].val * inv[N] % MOD)]
for i in range(N):
    fro, node, val = stack[i]
    node.val = val * node.ndesc * inv[max(1, N - node.ndesc)] % MOD
    for neigh in node.neighs:
        if neigh.ind == fro:
            continue
        stack.append((node.ind, neigh, node.val))

for i in range(N):
    print(nodes[i].val)

Buggy submission (verdict: Runtime Error):
import sys

sys.setrecursionlimit(10 ** 5 + 10)

MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 + 1):
    inv.append(MOD - MOD // i * inv[MOD % i] % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []

    def calc(self, fro):
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.calc(self.ind)
            self.val = self.val * neigh.val * ifact[neigh.ndesc] % MOD
            self.ndesc += neigh.ndesc
        self.val = self.val * fact[self.ndesc - 1] % MOD

    def comp(self, fro, carry):
        self.val = carry * self.ndesc * inv[max(1, N - self.ndesc)] % MOD
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.comp(self.ind, self.val)


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])
nodes[0].calc(0)
nodes[0].comp(0, (nodes[0].val * inv[N]) % MOD)
for i in range(N):
    print(nodes[i].val)

Buggy submission (verdict: Runtime Error):
import sys

sys.setrecursionlimit(10 ** 5 * 2)

MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 + 1):
    inv.append(MOD - MOD // i * inv[MOD % i] % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []

    def calc(self, fro):
        subdescs = []
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.calc(self.ind)
            self.val *= neigh.val
            self.ndesc += neigh.ndesc
            subdescs.append(neigh.ndesc)
        self.val = self.val * fact[self.ndesc - 1] % MOD
        for subdesc in subdescs:
            self.val = self.val * ifact[subdesc] % MOD

    def comp(self, fro, carry):
        self.val = carry * self.ndesc * inv[max(1, N - self.ndesc)] % MOD
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.comp(self.ind, self.val)


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])
nodes[0].calc(0)
nodes[0].comp(0, (nodes[0].val * inv[N]) % MOD)
for i in range(N):
    print(nodes[i].val)

Buggy submission (verdict: Runtime Error):
import sys

sys.setrecursionlimit(10 ** 5 + 10)

MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 + 1):
    inv.append(MOD - MOD // i * inv[MOD % i] % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []

    def calc(self, fro):
        subdescs = []
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.calc(self.ind)
            self.val *= neigh.val
            self.ndesc += neigh.ndesc
            subdescs.append(neigh.ndesc)
        self.val = self.val * fact[self.ndesc - 1] % MOD
        for subdesc in subdescs:
            self.val = self.val * ifact[subdesc] % MOD

    def comp(self, fro, carry):
        self.val = carry * self.ndesc * inv[max(1, N - self.ndesc)] % MOD
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.comp(self.ind, self.val)


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])
nodes[0].calc(0)
nodes[0].comp(0, (nodes[0].val * inv[N]) % MOD)
for i in range(N):
    print(nodes[i].val)

Buggy submission (verdict: Runtime Error):
MOD = 10 ** 9 + 7
inv = [None, 1]
for i in range(2, 10 ** 5 + 1):
    inv.append((MOD - MOD // i * inv[MOD % i]) % MOD)

fact = [1]
ifact = [1]
for i in range(1, 10 ** 5 + 1):
    fact.append((i * fact[-1]) % MOD)
    ifact.append((inv[i] * ifact[-1]) % MOD)


class Node:
    def __init__(self, ind):
        self.ind = ind
        self.val = 1
        self.ndesc = 1
        self.neighs = []

    def calc(self, fro):
        subdescs = []
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.calc(self.ind)
            self.val *= neigh.val
            self.ndesc += neigh.ndesc
            subdescs.append(neigh.ndesc)
        self.val = self.val * fact[self.ndesc - 1] % MOD
        for subdesc in subdescs:
            self.val = self.val * ifact[subdesc] % MOD

    def comp(self, fro, carry):
        self.val = carry * self.ndesc * inv[max(1, N - self.ndesc)] % MOD
        for neigh in self.neighs:
            if neigh.ind == fro:
                continue
            neigh.comp(self.ind, self.val)


N = int(input())
nodes = [Node(i) for i in range(N)]
for _ in range(N - 1):
    a, b = map(int, input().split())
    nodes[a - 1].neighs.append(nodes[b - 1])
    nodes[b - 1].neighs.append(nodes[a - 1])
nodes[0].calc(0)
nodes[0].comp(0, (nodes[0].val * inv[N]) % MOD)
for i in range(N):
    print(nodes[i].val)