SOURCE

const A = [1,2,3];
const B = [4,5,6];
const C = [7,8,9];

const total = {A,B,C,D:{
    id:1,
    child:{
        id:2,
        name:'xx'
    }
}};

function test(num){
    
    for(let item in total){
        if(total[item].includes(num))
        return item
    }
    return 0
}

console.log(test(5))


function deepClone(object){
    let cloneData;
    if(Array.isArray(object)){
        cloneData = [];
        object.forEach(e=>{
            cloneData.push(deepClone(e))
        })
    }else if(typeof object === 'object'){
        cloneData = {};
        for(let item in object){
            cloneData[item] = object[deepClone(item)]
        }
    }else{
        cloneData = object;
    }
}

let num = 123;

let copytotal = deepClone(total)
console.log(total === copytotal)