//Last occurence of a substring. position = str.lastIndexOf('is'); console.log(position);//output: 5. /* last time 'is' is found at 5th position. i is at 2 , s at 3 and space at 4 and i at 5 , s at 6.

Where to find the string functions? All functions are in the string-handling.js file inside the js folder.