[рони]

Volonter,

let period = {
            id: Math.floor(Math.random() * 1000000),
            date: new Date().toISOString(),
            unit: {
                1: {
                    a: '',
                    c: [16, 9, 3, 11, 30],
                    p: ''
                },
                2: {
                    a: '',
                    c: [5, 12, 8, 21, 33],
                    p: ''
                },
                3: {
                    a: '',
                    c: [6, 13, 10, 22, 34],
                    p: ''
                }
            }
        };

        let num = [16, 9, 3, 11, 30, 5, 12, 8, 21, 33, 6, 13, 10, 22, 34, 8, 69, 25, 47, 72, 18];

        function checkPeriod(num, { unit }) {
            let all = [];
            for (let i in unit) {
                all.push(...unit[i].c)
            };
            for (let i = num.length - 1; i ; i--) {all.includes(num[i]) && num.splice(i, 1)}
            return num
        }
        console.log(checkPeriod(num, period)) //[ 69, 25, 47, 72, 18];