updated calc logic

index.html

@@ -28,10 +28,10 @@
         <button class="number" id="number-3">3</button>
       </div>
       <div class="row operations">
-        <!-- <button id="add">+</button>
+        <button id="add">+</button>
         <button id="subtract">-</button>
         <button id="multiply">*</button>
-        <button id="divide">/</button> -->
+        <button id="divide">/</button>
       </div>
       <div class="row last-row">
         <button id="clear">C</button>

script.js

@@ -0,0 +1,74 @@
+const numbers = document.querySelectorAll(".number");
+const display = document.querySelector(".display");
+numbers.forEach((number) => {
+  number.addEventListener("click", () => {
+    display.textContent += number.textContent;
+  });
+});
+
+const addButton = document.getElementById("add");
+const subtractButton = document.getElementById("subtract");
+const multiplyButton = document.getElementById("multiply");
+const divideButton = document.getElementById("divide");
+const clearButton = document.getElementById("clear");
+const equalsButton = document.getElementById("equal");
+
+addButton.addEventListener("click", () => {
+  display.textContent += "+";
+});
+subtractButton.addEventListener("click", () => {
+  display.textContent += "-";
+});
+multiplyButton.addEventListener("click", () => {
+  display.textContent += "*";
+});
+divideButton.addEventListener("click", () => {
+  display.textContent += "/";
+});
+clearButton.addEventListener("click", () => {
+  display.textContent = "";
+});
+equalsButton.addEventListener("click", () => {
+
+  const expression = display.textContent;
+  const parts = expression.split(/([+\-*/])/);
+
+  parts.forEach((part, i) => {
+
+   if(part == "*") {
+    const prevNumber = parseFloat(parts[i - 1]);
+    const nextNumber = parseFloat(parts[i + 1]);
+    const result = prevNumber * nextNumber;
+    parts.splice(i - 1, 3, result);
+    i -= 2; 
+
+   } else if(part == "/") {
+     const prevNumber = parseFloat(parts[i - 1]);
+     const nextNumber = parseFloat(parts[i + 1]);
+      if (nextNumber === 0) {
+        display.textContent = "Error";
+        return;
+      }
+      const result = prevNumber / nextNumber;
+      parts.splice(i - 1, 3, result);
+      i -= 2; 
+   }
+  });
+
+  parts.forEach((part, i) => {
+    if (part == "+") {
+      const prevNumber = parseFloat(parts[i - 1]);
+      const nextNumber = parseFloat(parts[i + 1]);
+      const result = prevNumber + nextNumber;
+      parts.splice(i - 1, 3, result);
+      i -= 2;
+    } else if (part == "-") {
+      const prevNumber = parseFloat(parts[i - 1]);
+      const nextNumber = parseFloat(parts[i + 1]);
+      const result = prevNumber - nextNumber;
+      parts.splice(i - 1, 3, result);
+      i -= 2;
+    }
+  });
+  display.textContent = parts[0];
+});