lastindexof

lastIndexOf is a built-in function in many programming languages that returns the index of the last occurrence of a specific element or substring in a given string or array. It starts searching from the end of the string or array and returns -1 if the element or substring is not found.

For example, in JavaScript:

let str = "hello world";
console.log(str.lastIndexOf("o")); // outputs 7
console.log(str.lastIndexOf("l")); // outputs 9
console.log(str.lastIndexOf("x")); // outputs -1

In Java:

String str = "hello world";
System.out.println(str.lastIndexOf("o")); // outputs 7
System.out.println(str.lastIndexOf("l")); // outputs 9
System.out.println(str.lastIndexOf("x")); // outputs -1