Buggy python submission (verdict: Runtime Error):
class BTree:
    def __init__(self):
        self.value = None
        self.left = None
        self.right = None

    def insert(self, s):
        if self.value is None:
            self.value = s
        else:
            if self.value < s:
                if self.right is None:
                    self.right = BTree().insert(s)
                else:
                    self.right = self.right.insert(s)
            elif s < self.value:
                if self.left is None:
                    self.left = BTree().insert(s)
                else:
                    self.left = self.left.insert(s)
        return self

    def find(self, s):
        if self.value == s:
            return True
        elif self.value < s:
            if self.right is None:
                return False
            else:
                return self.right.find(s)
        else:
            if self.left is None:
                return False
            else:
                return self.left.find(s)


n = int(input())
tree = BTree()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        tree = tree.insert(command[1])
    elif command[0] == "find":
        if tree.find(command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")

Buggy python submission (verdict: Runtime Error):
class BTree:
    def __init__(self):
        self.value = "ZZZ"
        self.left = None
        self.right = None

    def insert(self, s):
        if self.value is None:
            self.value = s
        else:
            if self.value < s:
                if self.right is None:
                    self.right = BTree().insert(s)
                else:
                    self.right = self.right.insert(s)
            elif s < self.value:
                if self.left is None:
                    self.left = BTree().insert(s)
                else:
                    self.left = self.left.insert(s)
        return self

    def find(self, s):
        if self.value == s:
            return True
        elif self.value < s:
            if self.right is None:
                return False
            else:
                return self.right.find(s)
        else:
            if self.left is None:
                return False
            else:
                return self.left.find(s)


n = int(input())
tree = BTree()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        tree = tree.insert(command[1])
    elif command[0] == "find":
        if tree.find(command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")

Buggy python submission (verdict: Runtime Error):
class BTree:
    def __init__(self):
        self.value = "ZZZ"
        self.left = None
        self.right = None

    def insert(self, s):
        if self.value is None:
            self.value = s
        else:
            if self.value < s:
                if self.right is None:
                    self.right = BTree().insert(s)
                else:
                    self.right = self.right.insert(s)
            elif s < self.value:
                if self.left is None:
                    self.left = BTree().insert(s)
                else:
                    self.left = self.left.insert(s)
        return self

    def find(self, s):
        if self.value == s:
            return True
        elif self.value < s:
            if self.right is None:
                return False
            else:
                return self.right.find(s)
        else:
            if self.left is None:
                return False
            else:
                return self.left.find(s)


n = int(input())
tree = BTree()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        tree = tree.insert(command[1])
    elif command[0] == "find":
        if tree.find(command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")

Buggy python submission (verdict: Time Limit Exceeded):
class BTree:
    def __init__(self):
        self.value = "ZZZ"
        self.left = None
        self.right = None

    def insert(self, s):
        if self.value is "ZZZ":
            self.value = s
        else:
            if self.value < s:
                if self.right is None:
                    self.right = BTree().insert(s)
                else:
                    self.right = self.right.insert(s)
            elif s < self.value:
                if self.left is None:
                    self.left = BTree().insert(s)
                else:
                    self.left = self.left.insert(s)
        return self

    def find(self, s):
        if self.value == s:
            return True
        elif self.value < s:
            if self.right is None:
                return False
            else:
                return self.right.find(s)
        else:
            if self.left is None:
                return False
            else:
                return self.left.find(s)


n = int(input())
tree = BTree()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        tree = tree.insert(command[1])
    elif command[0] == "find":
        if tree.find(command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")

Buggy python submission (verdict: Time Limit Exceeded):
def find(data, s):
    l = 0
    r = len(data)
    while l < r:
        ind = (l + r) // 2
        if data[ind] == s:
            return True
        elif data[ind] < s:
            l = ind + 1
        else:
            r = ind
    return False

n = int(input())
data = []
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.append(command[1])
        data.sort()
    elif command[0] == "find":
        if find(data, command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")

Buggy python submission (verdict: Time Limit Exceeded):
def find(data, s):
    l = 0
    r = len(data)
    while l < r:
        ind = (l + r) // 2
        if data[ind] == s:
            return True
        elif data[ind] < s:
            l = ind + 1
        else:
            r = ind
    return False


def insert(data, s):
    if len(data) == 0:
        data.append(s)
    else:
        for i in range(len(data)):
            if s <= data[i]:
                data.insert(i, s)
                return data
        data.append(s)
    return data


n = int(input())
data = []
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data = insert(data, command[1])
    elif command[0] == "find":
        if find(data, command[1]):
            print("yes")
        else:
            print("no")


Fixed submission:
n = int(input())
data = set()
for _ in range(n):
    command = input().split()
    if command[0] == "insert":
        data.add(command[1])
    elif command[0] == "find":
        if command[1] in data:
            print("yes")
        else:
            print("no")