Create calculator_with_history.py

creating new program

Author: jas023

calculator_with_history.py

@@ -0,0 +1,77 @@
+# Calculator with history
+HISTORY_FILE = "history.txt"
+
+def show_history():
+    try:
+        with open(HISTORY_FILE, 'r') as file:
+            lines = file.readlines()
+        if len(lines) == 0:
+            print("No history found")
+        else:
+            print("\n--- Calculation History ---")
+            for line in reversed(lines):   # show most recent first
+                print(line.strip())
+    except FileNotFoundError:
+        print("No history file found yet")
+
+def clear_history():
+    with open(HISTORY_FILE, 'w') as file:
+        pass
+    print("History is cleared")
+
+def save_to_history(eq, result):
+    with open(HISTORY_FILE, 'a') as file:
+        file.write(eq + " = " + str(result) + "\n")
+
+def calculator(user_input):
+    parts = user_input.split()
+    if len(parts) != 3:
+        print("Invalid input! Use syntax: number operator number")
+        return
+
+    try:
+        n1 = float(parts[0])
+        n2 = float(parts[2])
+    except ValueError:
+        print("Invalid numbers!")
+        return
+
+    op = parts[1]
+
+    if op == '+':
+        result = n1 + n2
+    elif op == '-':
+        result = n1 - n2
+    elif op == '*':
+        result = n1 * n2
+    elif op == '/':
+        if n2 == 0:
+            print("Error: Division by zero")
+            return
+        result = n1 / n2
+    else:
+        print("Invalid operator! Use + - * /")
+        return
+
+    # if result has no decimals, make it integer
+    if int(result) == result:
+        result = int(result)
+
+    print("Result:", result)
+    save_to_history(user_input, result)
+
+def main():
+    print("------- Welcome to Simple Calculator with History -------")
+    while True:
+        user_input = input("\nEnter calculation using ( +, - , *, / ) or command (history, clear, exit): ").strip().lower()
+        if user_input == 'exit':
+            print("Thank you for using the calculator!")
+            break
+        elif user_input == 'history':
+            show_history()
+        elif user_input == 'clear':
+            clear_history()
+        else:
+            calculator(user_input)
+
+main()