ES5的寫法
var a = [1,2,3,4,5]
var b = [2,4,6,8,10]
// //交集
var c = a.filter(function(v){ return b.indexOf(v) > -1 })
// //差集
var d = a.filter(function(v){ return b.indexOf(v) == -1 })
// //補集
var e = a.filter(function(v){ return !(b.indexOf(v) > -1) })
.concat(b.filter(function(v){ return !(a.indexOf(v) > -1)}))
//並集
var f = a.concat(b.filter(function(v){ return !(a.indexOf(v) > -1)}));
console.log("數組a:", a);
console.log("數組b:", b);
console.log("a與b的交集:", c);
console.log("a與b的差集:", d);
console.log("a與b的補集:", e);
console.log("a與b的並集:", f);
用ES6 的寫法
var a = [1,2,3,4,5] var b = [2,4,6,8,10] console.log("數組a:", a); console.log("數組b:", b); var sa = new Set(a); var sb = new Set(b); // 交集 let intersect = a.filter(x => sb.has(x)); // 差集 let minus = a.filter(x => !sb.has(x)); // 補集 let complement = [...a.filter(x => !sb.has(x)), ...b.filter(x => !sa.has(x))]; // 並集 let unionSet = Array.from(new Set([...a, ...b])); console.log("a與b的交集:", intersect); console.log("a與b的差集:", minus); console.log("a與b的補集:", complement); console.log("a與b的並集:", unionSet);