Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections
def solve():
    sys.setrecursionlimit(100000)
    mod = 998244353

    N = int(input())
    D = list(map(int, input().split()))
    cnter = collections.Counter(D)
    cnter = sorted(cnter.items())

    ans = 1
    if cnter[0][0] != 0 or cnter[0][1] != 1 : 
        ans = 0
    elif cnter[1][0] != 1:
        ans = 0
    else:
        for i in range(2, len(cnter)):
            if cnter[i][0] != i:
                ans = 0
                break

            else:
                ans = ans * modpow(cnter[i-1][1], cnter[i][1], mod) % mod
    
    print(ans)


def modpow(a, b, mod):
    res = 1
    while b > 0:
        if b & 1:
            res = res * a % mod
            a = a * a % mod
            b = b >> 1
    return res

if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections
def solve():
    sys.setrecursionlimit(100000)
    mod = 998244353

    N = int(input())
    D = list(map(int, input().split()))
    ans = 1
    if D[0] != 0:
        ans = 0
        print(ans)
        exit(0)
    
    cnter = collections.Counter(D)
    cnter = sorted(cnter.items())

    if cnter[0][0] != 0 or cnter[0][1] != 1 : 
        ans = 0
    elif len(cnter) == 1:
        ans = 1
    elif cnter[1][0] != 1:
        ans = 0
    else:
        for i in range(2, len(cnter)):
            if cnter[i][0] != i:
                ans = 0
                break

            else:
                ans = ans * modpow(cnter[i-1][1], cnter[i][1], mod) % mod
    
    print(ans)


def modpow(a,n,p):
  bi=str(format(n,"b"))
  res=1
  for i in range(len(bi)):
    res=(res*res) %p
    if bi[i]=="1":
      res=(res*a) %p
  return res

if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections
def solve():
    sys.setrecursionlimit(100000)
    mod = 998244353

    N = int(input())
    D = list(map(int, input().split()))
    cnter = collections.Counter(D)
    cnter = sorted(cnter.items())

    ans = 1
    if cnter[0][0] != 0 or cnter[0][1] != 1 : 
        ans = 0
    elif cnter[1][0] != 1:
        ans = 0
    else:
        for i in range(2, len(cnter)):
            if cnter[i][0] != i:
                ans = 0
                break

            else:
                ans = ans * modpow(cnter[i-1][1], cnter[i][1], mod) % mod
    
    print(ans)


def modpow(a, b, mod):
    res = 1
    while b > 0:
        if b & 1:
            res = res * a % mod
            a = a * a % mod
            b = b >> 1
    return res

if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections
def solve():
    sys.setrecursionlimit(100000)
    mod = 998244353

    N = int(input())
    D = list(map(int, input().split()))
    ans = 1
    if D[0] != 0:
        ans = 0
        print(ans)
        exit(0)
    
    cnter = collections.Counter(D)
    cnter = sorted(cnter.items())

    if cnter[0][0] != 0 or cnter[0][1] != 1 : 
        ans = 0
    elif len(cnter) == 1:
        ans = 1
    elif cnter[1][0] != 1:
        ans = 0
    else:
        for i in range(2, len(cnter)):
            if cnter[i][0] != i:
                ans = 0
                break

            else:
                ans = ans * modpow(cnter[i-1][1], cnter[i][1], mod) % mod
    
    print(ans)


def modpow(a,n,p):
  bi=str(format(n,"b"))
  res=1
  for i in range(len(bi)):
    res=(res*res) %p
    if bi[i]=="1":
      res=(res*a) %p
  return res

if __name__ == '__main__':
    solve()