Flat a JS object

flat.js

// Receive an 
const flatArray = (key,list)=>{

	let obj={};

	list.forEach((item,i)=>{
		obj[`${key}.${i}`]=item;
	});

	return obj;

}

// Declare a flatten function that takes
// object as parameter and returns the
// flatten object
const flattenObj = (ob) => {
 
    // The object which contains the
    // final result
    let result = {};
 
    // loop through the object "ob"
    for (const i in ob) {
 
        // We check the type of the i using
        // typeof() function and recursively
        // call the function again
        if ((typeof ob[i]) === 'object' && !Array.isArray(ob[i])) {
            const temp = flattenObj(ob[i]);
            for (const j in temp) {
 
                // Store temp in result
                result[i + '.' + j] = temp[j];
            }
        }
 
        // Else store ob[i] in result directly
        else {

						if (Array.isArray(ob[i])&&ob[i].length>0){
							const flatList = flatArray(i,ob[i]);
							result={
								...result,
								...flatList
							};
						}
            else
              result[i] = ob[i];
        }
    }
    return result;
};

let obj = {
    Company: "GeeksforGeeks",
    Address: "Noida",
    pepe:[1,2,3,4],
    contact: +91 - 999999999,
    mentor: {
        HTML: "GFG",
        CSS: "GFG",
        JavaScript: "GFG"
		},
		books:{
			colors:['red','green']
		}
};

console.log(obj);
console.log(flattenObj(obj))
console.log(flatArray('tmp',[1,2,3,4]))