Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        Flag = 0
        for j in range(N):
            if S[j] == lucky[Flag]:
                Flag += 1
            if Flag == 3:
                count += 1
                break
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        Flag_j, Flag_m, Flag_n = -1, -1, -1
        # print("check001")

        for j in range(N-2):
            if S[j] == lucky[0]:
                Flag_j = j
                break
        # print("check002")
        if Flag_j == -1:
            continue
        # print("check003")

        for m in range(Flag_j+1, N-1):
            if S[m] == lucky[1]:
                Flag_m = m
                break
        # print("check004")
        if Flag_m == -1:
            continue
        # print("check005")

        for n in range(Flag_m+1, N):
            if S[n] == lucky[2]:
                Flag_n = n
                break
        # print("check006")
        if Flag_n == -1:
            continue
        # print("check007")
        count += 1

    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = "000"
        Flag_j = -1
        Flag_m = -1
        Flag_n = -1
        # print("check001")
        if i < 10:
            lucky = "00" + str(i)
        elif i < 100:
            lucky = "0" + str(i)
        else:
            lucky = str(i)

        for j in range(N-2):
            if S[j] == lucky[0]:
                Flag_j = j
                break
        # print("check002")
        if Flag_j == -1:
            continue
        # print("check003")

        for m in range(Flag_j+1, N-1):
            if S[m] == lucky[1]:
                Flag_m = m
                break
        # print("check004")
        if Flag_m == -1:
            continue
        # print("check005")

        for n in range(Flag_m+1, N):
            if S[n] == lucky[2]:
                Flag_n = n
                break
        # print("check006")
        if Flag_n == -1:
            continue
        # print("check007")
        count += 1

    print(count)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = "000"
        Flag_j = -1
        Flag_m = -1
        Flag_n = -1
        # print("check001")
        if i < 10:
            lucky = "00" + str(i)
        elif i < 100:
            lucky = "0" + str(i)
        else:
            lucky = str(i)

        for j in range(N):
            if S[j] == lucky[0]:
                Flag_j = j
                break
        # print("check002")
        if Flag_j == -1:
            continue
        # print("check003")

        for m in range(Flag_j+1, N):
            if S[m] == lucky[1]:
                Flag_m = m
                break
        # print("check004")
        if Flag_m == -1:
            continue
        # print("check005")

        for n in range(Flag_m+1, N):
            if S[n] == lucky[2]:
                Flag_n = n
                break
        # print("check006")
        if Flag_n == -1:
            continue
        # print("check007")
        count += 1

    print(count)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    array = []
    for i in range(N):
        for j in range(i+1, N):
            Marray = []
            for m in range(j+1, N):
                Marray.append(S[m])
                Marray = list(set(Marray))
                if len(Marray) == 10:
                    break
                num = S[i] + S[j] + S[m]
                array.append(num)
                if len(array) >= 1000:
                    array = list(set(array))
                    if len(array) == 999:
                        print("999")
                        return
    array = set(array)
    print(len(array))


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    array = []
    for i in range(N):
        for j in range(i+1, N):
            Marray = []
            for m in range(j+1, N):
                Marray.append(S[m])
                Marray = list(set(Marray))
                if len(Marray) == 10:
                    break
                num = S[i] + S[j] + S[m]
                array.append(num)
    array = set(array)
    print(len(array))


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    N = sc.intarr()[0]
    S = sc.strarr()[0]

    array = []
    for i in range(N):
        for j in range(i+1, N):
            for m in range(j+1, N):
                num = S[i] + S[j] + S[m]
                array.append(num)
    array = set(array)
    print(len(array))


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()


Fixed submission:
import sys
import math
input = sys.stdin.readline


def main():
    sc = Scan()
    _ = sc.intarr()[0]
    S = sc.strarr()[0]

    count = 0

    for i in range(1000):
        # print("--------")
        lucky = format_str(i)
        first = S.find(lucky[0])
        third = S.rfind(lucky[2])

        if first == -1 or third == -1:
            continue
        elif first < third:
            if lucky[1] in S[first + 1:third]:
                count += 1
    print(count)


def format_str(num):
    if num < 10:
        return "00" + str(num)
    elif num < 100:
        return "0" + str(num)
    else:
        return str(num)


class Scan():

    def intarr(self):
        line = input()
        array = line.split(' ')
        num_array = [int(n) for n in array]
        return num_array

    def intarr_ver(self, n):
        return [int(input()) for _ in range(n)]

    def strarr(self):
        line = input()
        array = line.split(' ')
        array[-1] = array[-1].strip('\n')
        return array


def display(array):
    for a in range(len(array)):
        if len(array) - a != 1:
            print(array[a], end=' ')
        else:
            print(array[a])


main()