Buggy python submission (verdict: Time Limit Exceeded):
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
a = [i for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if int(j) == num[p]:
            p += 1
            if p == 3:
                res += 1
                break
print(res)

Fixed submission:
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
a = [str(i) for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if j == num[p]:
            p += 1
            if p == 3:
                break
    if p == 3:
        res += 1
print(res)

Buggy python submission (verdict: Runtime Error):
n = inp()
s = input()
res = 0
a = [str(i) for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if j == num[p]:
            p += 1
            if p == 3:
                break
    if p == 3:
        res += 1
print(res)

Fixed submission:
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
a = [str(i) for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if j == num[p]:
            p += 1
            if p == 3:
                break
    if p == 3:
        res += 1
print(res)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
for num in itertools.product(range(10), repeat=3):
    p = 0
    for i,j in enumerate(s):
        if int(j) == num[p]:
            p += 1
            if p == 3:
                res += 1
                break
print(res)

Fixed submission:
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
a = [str(i) for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if j == num[p]:
            p += 1
            if p == 3:
                break
    if p == 3:
        res += 1
print(res)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
for num in itertools.product(range(10), repeat=3):
    p = 0
    for i in range(n):
        if int(s[i]) == num[p]:
            p += 1
            if p == 3:
                res += 1
                break
print(res)

Fixed submission:
from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
import sys,bisect,math,itertools,fractions,pprint
sys.setrecursionlimit(10**8)
mod = 10**9+7
mod2 = 998244353
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpln(n): return list(int(sys.stdin.readline()) for i in range(n))

n = inp()
s = input()
res = 0
a = [str(i) for i in range(10)]
for num in itertools.product(a, repeat=3):
    p = 0
    for i,j in enumerate(s):
        if j == num[p]:
            p += 1
            if p == 3:
                break
    if p == 3:
        res += 1
print(res)