1//see https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Objets_globaux/Array/unshift
2
3const array1 = [1, 2, 3];
4
5console.log(array1.unshift(4, 5));
6// expected output: 5
7
8console.log(array1);
9// expected output: Array [4, 5, 1, 2, 3]
1var a = [23, 45, 12, 67];
2a.unshift(34);
3console.log(a); // [34, 23, 45, 12, 67]