js startswith

var str = "Hello world, welcome to the universe.";
var n = str.startsWith("Hello");const str = "Saturday night plans";
const res = str.startsWith("Sat");
console.log(res); //> trueconst str1 = 'Saturday night plans';

console.log(str1.startsWith('Sat'));
// expected output: true

console.log(str1.startsWith('Sat', 3));
// expected output: false
//checks if a string starts with a word
function startsWith(str, word) {
    return str.lastIndexOf(word, 0) === 0;
}
startsWith("Welcome to earth.","Welcome"); //true