Though it would seem pretty simple, but as soon as you try to add a JavaScript to your WordPress post which is more than few lines of code. WordPress somehow messes up the code and the script will not work due to wordpress formatting it. You can disable formatting but then other old posts also loose formatting. The other solution provided is to add them to template / make JS files and include them. Both require more work.
Here is my little solution , Basically pack the script and make it as a one line of code which can be added to the html editor –
Go to the following link paste your JavaScript code and embed the WordPress embed in your wordpress …