function plusMinus(arr) {
    let [pos, neg, zer] = [0,0,0];
    for(let i = 0; i < arr.length; i++){
        if(arr[i] > 0)pos++;
        else if(arr[i] < 0)neg++;
        else if(arr[i] === 0) zer++;
    }
    let ratios = [pos, neg, zer];
    ratios.forEach(val => {
        console.log((val/arr.length).toFixed(6));
    })
}