feat: basic js complete

calculator/js/script.js

@@ -0,0 +1,37 @@
+let firstNum = undefined
+let secondNum = undefined
+let operator = undefined
+
+function add(x, y) {
+    return Number(x + y);
+}
+
+function subtract(x, y) {
+    return x - y;
+}
+
+function multiply(x, y) {
+    return x * y;
+}
+
+function divive(x, y) {
+    if (x === 0) {
+        return 0
+    } else if (y === 0) {
+        alert("Cannot divide by 0!");
+    }
+    return x / y;
+}
+
+function operate(firstNum, secondNum, operator) {
+    switch (operator) {
+        case '+':
+            return add(firstNum, secondNum);
+        case '-':
+            return subtract(firstNum, secondNum);
+        case '*':
+            return multiply(firstNum, secondNum);
+        case '/':
+            return divive(firstNum, secondNum);
+    }
+}