Javascript: add hint to Replacing If Else Chains with Switch (#19116)

Add hint to Replacing If Else Chains with Switch (https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/replacing-if-else-chains-with-switch/ and https://guide.freecodecamp.org/certifications/javascript-algorithms-and-data-structures/basic-javascript/replacing-if-else-chains-with-switch/)

client/src/pages/guide/english/certifications/javascript-algorithms-and-data-structures/basic-javascript/replacing-if-else-chains-with-switch/index.md

@@ -1,10 +1,116 @@
----
-title: Replacing If Else Chains with Switch
----
+
 ## Replacing If Else Chains with Switch
 
-This is a stub. <a href='https://github.com/freecodecamp/guides/tree/master/src/pages/certifications/javascript-algorithms-and-data-structures/basic-javascript/replacing-if-else-chains-with-switch/index.md' target='_blank' rel='nofollow'>Help our community expand it</a>.
-
-<a href='https://github.com/freecodecamp/guides/blob/master/README.md' target='_blank' rel='nofollow'>This quick style guide will help ensure your pull request gets accepted</a>.
-
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+
+Here’s the setup:
+
+```javascript
+function chainToSwitch(val) {
+  var answer = "";
+  // Only change code below this line
+  switch(val) {
+    case "bob":
+        answer = "Marley";
+        break;
+    case 42:
+        answer = "The Answer";
+        break;
+    case 1:
+        answer = "There is no #1";
+        break;
+    case 99:
+        answer = "Missed me by this much!";
+        break;
+    case 7:
+        answer = "Ate Nine";
+        break;
+  }
+  // Only change code above this line  
+  return answer;  
+}
+// Change this value to test
+chainToSwitch(7);
+```
+
+We need to change the chained ```if/else if``` statements into a ```switch``` statement.
+
+ Here’s a solution:
+ 
+ Now, we need to comment (```//``` - select all lines and ```ctrl+/```) all chained ```if/else if``` statements:
+ 
+ ```javascript
+ //   if (val === "bob") {
+//     answer = "Marley";
+//   } else if (val === 42) {
+//     answer = "The Answer";
+//   } else if (val === 1) {
+//     answer = "There is no #1";
+//   } else if (val === 99) {
+//     answer = "Missed me by this much!";
+//   } else if (val === 7) {
+//     answer = "Ate Nine";
+//   }
+ ```
+ 
+ Next, we need to create simple ```switch``` statement:
+ 
+ ```javascript
+ switch(val) {
+ } 
+ ```
+ 
+ and add in this ```switch``` statement ```case``` - for all ```if/else if``` statement (just copy it from our commented code above):
+ 
+  ```javascript
+  switch(val) {
+    case "bob":
+        answer = "Marley";
+        break;
+    case 42:
+        answer = "The Answer";
+        break;
+    case 1:
+        answer = "There is no #1";
+        break;
+    case 99:
+        answer = "Missed me by this much!";
+        break;
+    case 7:
+        answer = "Ate Nine";
+        break;
+  }
+  ``` 
+ 
+ Dont forget to use ```break``` in each ```case```!
+ Now, we can delete commented code with ```if/else if``` statement above.
+ 
+ Here’s a full solution:
+ 
+ ```javascript
+ function chainToSwitch(val) {
+  var answer = "";
+  // Only change code below this line
+  switch(val) {
+    case "bob":
+        answer = "Marley";
+        break;
+    case 42:
+        answer = "The Answer";
+        break;
+    case 1:
+        answer = "There is no #1";
+        break;
+    case 99:
+        answer = "Missed me by this much!";
+        break;
+    case 7:
+        answer = "Ate Nine";
+        break;
+  } 
+  // Only change code above this line  
+  return answer;  
+}
+// Change this value to test
+chainToSwitch(7);
+ ```