javascript -reduce

developer.mozilla.org

sample code

let arr1 = [1,2,3,4,5]
console.log(arr1.reduce((a, b) => { return a + b }));         // sum:15
console.log(arr1.reduce((a, b) => { return a  > b ? a : b})); // max:5
console.log(arr1.reduce((a, b) => { return a < b ? a : b}));  // min:1