Buggy python submission (verdict: Runtime Error):
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append('end')
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        if c == 0:
            print(0)
            exit();
        ll.append(c)
        c = 0
    c+=1
   
count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Fixed submission:
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

for i in range(1, n):
    if l[i] == 0:
        print(0)
        exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append(-4)
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        if l[i] != l[i+1]-1 and l[i+1] > 0:
            print(0)
            exit()
        ll.append(c)
        c = 0
    c+=1

count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Buggy python submission (verdict: Runtime Error):
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append('end')
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        ll.append(c)
        c = 0
    c+=1
   
count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Fixed submission:
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

for i in range(1, n):
    if l[i] == 0:
        print(0)
        exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append(-4)
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        if l[i] != l[i+1]-1 and l[i+1] > 0:
            print(0)
            exit()
        ll.append(c)
        c = 0
    c+=1

count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Buggy python submission (verdict: Runtime Error):
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append('end')
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        ll.append(c)
        c = 0
    c+=1
   
count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Fixed submission:
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

for i in range(1, n):
    if l[i] == 0:
        print(0)
        exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append(-4)
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        if l[i] != l[i+1]-1 and l[i+1] > 0:
            print(0)
            exit()
        ll.append(c)
        c = 0
    c+=1

count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

max_vertex = max(l)
ll = []

for i in range(1, max_vertex+1):
    if l.count(i) == 0:
        print(0)
        exit()
    ll.append(l.count(i))

count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)

Fixed submission:
n = int(input()) 
l = list(map(int, input().split()))
if l[0] != 0:
    print(0)
    exit()

for i in range(1, n):
    if l[i] == 0:
        print(0)
        exit()

max_vertex = max(l)
ll = []
l=sorted(l)
l.append(-4)
c=1
for i in range(1, n):
    if l[i] != l[i+1]:
        if l[i] != l[i+1]-1 and l[i+1] > 0:
            print(0)
            exit()
        ll.append(c)
        c = 0
    c+=1

count = 1
for i in range(1, max_vertex):
    tmp = ll[i-1]
    count *= pow(tmp, ll[i])
print(count%998244353)