diff --git a/challenges/01-calc.py b/challenges/01-calc.py
index 87f5190..e8a5946 100644
--- a/challenges/01-calc.py
+++ b/challenges/01-calc.py
@@ -2,3 +2,34 @@
 # input() always returns a string value. If you ever want someone
 # to enter a number you have to use the `int()` function to convert
 # what they typed in to a string.
+
+
+def calculator():
+    # Ask for the operation
+    operation = input("What do you want to do?(add, sub, mult, div)\n")
+
+    # Ask for the numbers
+    num1 = int(input("Num 1?\n"))
+    num2 = int(input("Num 2?\n"))
+
+    # Perform the calculation
+    if operation == 'add':
+        result = num1 + num2
+    elif operation == 'sub':
+        result = num1 - num2
+    elif operation == 'mult':
+        result = num1 * num2
+    elif operation == 'div':
+        if num2 != 0:
+            result = num1 / num2
+        else:
+            print("Error: Division by zero is not allowed.")
+            return
+    else:
+        print("Error: Invalid operation.")
+        return
+
+    # Print the result
+    print("Your result is " + str(result))
+
+calculator()
diff --git a/challenges/02-reverse.py b/challenges/02-reverse.py
index 8cf2677..9ba91c5 100644
--- a/challenges/02-reverse.py
+++ b/challenges/02-reverse.py
@@ -6,3 +6,13 @@
 # several ways to reverse a string, and it's a good read!
 #
 # http://www.techbeamers.com/essential-python-tips-tricks-programmers/?utm_source=mybridge&utm_medium=blog&utm_campaign=read_more#tip1
+
+def reverse(string):
+    reverse_string = ''
+    for i in range(len(string)-1, -1, -1):
+        reverse_string += string[i]
+    return reverse_string
+
+print(reverse('Supacalafircationstions'))
+
+print("hello world")
\ No newline at end of file
diff --git a/challenges/03-bank.py b/challenges/03-bank.py
index 554cb1d..88df952 100644
--- a/challenges/03-bank.py
+++ b/challenges/03-bank.py
@@ -1,3 +1,24 @@
 print("Welcome to Chase bank.")
 print("Have a nice day!")
 
+def prompt(account):
+    balance = 500
+    account = input("Do you want to see your balance, withdraw or deposit?")
+
+    if account == 'balance':
+        print('Your balance is', balance)
+    elif account == 'withdraw':
+        withdraw = int(input("How much would you like to withdraw?"))
+        if withdraw <= balance:
+            balance -= withdraw
+        else:
+            print("Insufficient balance.")
+    elif account == 'deposit':
+        deposit = int(input("How much would you like to deposit?"))
+        balance += deposit
+
+    return balance
+
+print(prompt("Egor"))
+        
+        
diff --git a/challenges/04-alphabetical.py b/challenges/04-alphabetical.py
index 5051ec4..a12e965 100644
--- a/challenges/04-alphabetical.py
+++ b/challenges/04-alphabetical.py
@@ -1,3 +1,10 @@
 # You'll need to use a couple of built in functions to alphabetize a string. 
 # Try to avoid looking up the exact answer and look at built in functions for
 # lists and strings instead.
+
+def alphabetize(string):
+    sorted_string = ''.join(sorted(string))
+    return sorted_string
+
+input_string = input("Give me a string to alphabetize\n")
+print('Alphabetized:', alphabetize(input_string))
\ No newline at end of file