Add files via upload

index.html

@@ -7,6 +7,7 @@
 <style>
     body {
         font-family: Arial, sans-serif;
+        background-image: url('background_image.jpg'); /* Replace 'background_image.jpg' with the path to your background image */
         background-size: cover;
         background-position: center;
         background-repeat: no-repeat;
@@ -47,6 +48,10 @@ <h3>Edit/Delete Options</h3>
     <script>
         function calculateFrequency() {
             var inputString = document.getElementById("inputString").value;
+            if (inputString.trim() === "") {
+                alert("Please enter a string.");
+                return;
+            }
             var frequency = {};
             for (var i = 0; i < inputString.length; i++) {
                 var char = inputString.charAt(i);
@@ -69,16 +74,32 @@ <h3>Edit/Delete Options</h3>
 
         function editCharacter() {
             var editCharacter = document.getElementById("editCharacter").value;
+            if (editCharacter.trim() === "") {
+                alert("Please enter the character to edit.");
+                return;
+            }
             var newCharacter = document.getElementById("newCharacter").value;
             var inputString = document.getElementById("inputString").value;
+            if (!inputString.includes(editCharacter)) {
+                alert("Character to edit is not present in the input string.");
+                return;
+            }
             var updatedString = inputString.replace(editCharacter, newCharacter);
             document.getElementById("inputString").value = updatedString;
             calculateFrequency();
         }
 
         function deleteCharacter() {
             var deleteCharacter = document.getElementById("deleteCharacter").value;
+            if (deleteCharacter.trim() === "") {
+                alert("Please enter the character to delete.");
+                return;
+            }
             var inputString = document.getElementById("inputString").value;
+            if (!inputString.includes(deleteCharacter)) {
+                alert("Character to delete is not present in the input string.");
+                return;
+            }
             var updatedString = inputString.split(deleteCharacter).join("");
             document.getElementById("inputString").value = updatedString;
             calculateFrequency();