test.ts

// const arr: number[] = [1, 3, 2, 5, 0];

const findProductOfArr = (arr: number[]): number => {
    let product: number = 1;

    arr.forEach(num => {
        if(num !== 0) product = product * num;
    });

    return product;
};

const getIdxsOfZeros = (arr: number[]): number[] | null => {
    const idxsOfZeros: number[] = [];

    arr.forEach((num, idx) => {
        if(num === 0) idxsOfZeros.push(idx)
    });

    return idxsOfZeros.length > 0 ? idxsOfZeros : null;
};

const fn: () => void = () => {
    const arr: number[] = [1, 2, 0, 4, 0];

    let resultArr: number[] = arr;
    const wholeArrProduct = findProductOfArr(arr);
    const zeroIdxs = getIdxsOfZeros(arr);

    if(zeroIdxs){
        resultArr = resultArr.fill(0);
        zeroIdxs.forEach(idx => {
            resultArr[idx] = wholeArrProduct;
        });
    } else {
        resultArr = arr.map(num => wholeArrProduct/num);
    }

    console.log(JSON.stringify(resultArr));
};

fn();