diff --git a/adder.py b/adder.py
new file mode 100644
index 0000000..97054d7
--- /dev/null
+++ b/adder.py
@@ -0,0 +1,9 @@
+import sys
+
+if __name__ == "__main__":
+    result = 0
+
+    for arg in sys.argv:
+        if(arg.isdecimal()):
+            result += int(arg)
+    print(result)
\ No newline at end of file
diff --git a/args.py b/args.py
new file mode 100644
index 0000000..cde3aec
--- /dev/null
+++ b/args.py
@@ -0,0 +1,6 @@
+import sys
+
+if __name__ == "__main__":
+    print(f"Arguments count: {len(sys.argv)}")
+    for i, arg in enumerate(sys.argv):
+        print(f"Argument {i:>6}: {arg}")
\ No newline at end of file
diff --git a/class-incest.py b/class-incest.py
new file mode 100644
index 0000000..747486a
--- /dev/null
+++ b/class-incest.py
@@ -0,0 +1,35 @@
+class Root():
+	a = "Root"
+	def f(self):
+		print(self.a)
+	pass
+
+class A(Root):
+	a = "A"
+	def f(self):
+		print(self.a)
+		super().f()
+	pass
+
+class B(Root):
+	a = "B"
+	def f(self):
+		print(self.a)
+		super().f()
+	pass
+
+class C(A, B):
+	# C is a child of A and B, which are siblings. Therefore incest.
+	# You may laugh now.
+	def f(self):
+		print("C")
+		super().f()
+		print(C.__mro__) # Method Resolution Order(MRO) 
+	pass
+
+def main():
+	o = C()
+	o.f()
+
+if __name__ == "__main__":
+	main()
diff --git a/hello.py b/hello.py
new file mode 100644
index 0000000..0f31502
--- /dev/null
+++ b/hello.py
@@ -0,0 +1,6 @@
+print("hello world!\n")
+for i in range(10):
+    if(i<9):
+        print((i)*"hello-"+"hello")
+    elif(i==0):
+        print("hello")
\ No newline at end of file
diff --git a/randomString.py b/randomString.py
new file mode 100644
index 0000000..f4285d9
--- /dev/null
+++ b/randomString.py
@@ -0,0 +1,11 @@
+import random
+import string
+
+
+def get_random_string(length):
+    # choose from all lowercase letter
+    letters = string.ascii_lowercase
+    result_str = ''.join(random.choice(letters) for i in range(length))
+    return result_str
+
+print(get_random_string(20))
diff --git a/simple-calc.py b/simple-calc.py
new file mode 100644
index 0000000..decb6a3
--- /dev/null
+++ b/simple-calc.py
@@ -0,0 +1,65 @@
+import sys
+
+if __name__ == "__main__":
+    result = 0
+
+    def help(): {
+        print("input: [value] [operation] [value]\noperations: [ + - . / ]\n")
+    }
+
+    if(len(sys.argv) > 1):
+            if(sys.argv[1] == "-h" or sys.argv[1] == "--help"):
+                help()
+                sys.exit()
+    if(len(sys.argv) == 0):
+        help()
+        sys.exit()
+
+    if(len(sys.argv) < 4):
+        print("not enough arguments\n")
+        help()
+        sys.exit()
+    if(len(sys.argv) > 4):
+        print("too many arguments\n")
+        help()
+        sys.exit()
+        
+    if(sys.argv[1].isdecimal):
+        val1=int(sys.argv[1])
+
+    else:
+        print("1st arg should be an integer!")
+        help()
+        sys.exit()
+    if(sys.argv[2].isascii and len(sys.argv[2]) == 1):
+        if (not ((sys.argv[2]=="+") or (sys.argv[2]=="-") or (sys.argv[2]==".") or (sys.argv[2]=="/"))):
+            print("2nd arg should be an operator [ + - . / ]!\n")
+            help()
+            sys.exit()
+        op=sys.argv[2]
+        
+    if(sys.argv[3].isdecimal):
+        val2=int(sys.argv[3])
+    else:
+        print("3rd arg should be an integer!")
+        help()
+
+
+    #todo switch case and then operations
+
+    if(op=="+"):
+        print(f"{val1} + {val2} = {val1+val2}")
+
+    elif(op=="-"):
+        print(f"{val1} - {val2} = {val1-val2}")
+
+    elif(op=="."):
+        print(f"{val1} . {val2} = {val1*val2}")
+
+    elif(op=="/"):
+        print(f"{val1} / {val2} = {val1/val2}")
+
+    else:
+        print(f"'{op}' is not a valid operator")
+        sys.exit()
+        
\ No newline at end of file