//includes
const list = [100, 200, 3, 2, 33, 882, 9098, 92933];
const result = list.reduce((pre, cur) => pre ? pre : cur === 2, false);
console.log(result);
// slice
const slice1 = list.reduce((pre, cur, index) => {
if (index >= 1 && index < 4) {
return [...pre, cur];
}
return pre;
}, []);
console.log(slice1);