Styjun

function plusMinus(arr) 
 var freq = 
 posetive: 0,
 negative: 0,
 zero: 0
 ;
 for (var i = 0; i < arr.length; i++)
 if( arr[i] < 0) 
 freq.negative++;
 else if(arr[i] > 0) 
 freq.posetive++;
 else 
 freq.zero++;
 
 
 for(var key in freq)
 console.log((freq[key]/arr.length).toFixed(6));
 

plusMinus([1,1,0,-1,-1]);

function plusMinus(arr) 
 var freq = 1: 0, '-1': 0, 0: 0 ,
 i, key;

 for (i = 0; i < arr.length; i++) 
 freq[arr[i]]++;
 

 for (key of [1, -1, 0]) 
 console.log((freq[key] / arr.length).toFixed(6));
 


plusMinus([1, 1, 0, -1, -1]);

let arr = [1,1,0,-1,-1]

let op = arr.reduce((op,inp)=>
 if(inp === 0)
 op.zero.count++
 else if (inp > 0)
 op.pos.count++;
 else 
 op.neg.count++;
 
 return op
,zero:count:0,pos:count:0,neg:count:0)


let final = Object.entries(op).map(([key,value])=>(
 [key] : value.count / arr.length
))

console.log(final)

const arr = [1, 1, 0, -1, -1];

const counts = arr.reduce((acc, curr) => 
 if (!curr) acc[0]++;
 else if (curr > 0) acc[1]++;
 else acc[2]++;
 return acc
, [0, 0, 0]);

const result = counts.map(e => e / arr.length).filter((e, i, a) => a.indexOf(e) == i);

console.log(result);

const array = [1,1,0,-1,-1];
function plusMinus(arr)
 const output = arr.reduce((acc, ele) => 
 if(ele > 0)
 if(ele < 0)
 acc[1] = ((acc[1] 
 if(ele === 0) 0 ) + 1 / arr.length);
 
 return acc;
 , []).map(ele => ele.toFixed(6));
 console.log(...output);

plusMinus(array);

const plusMinus = (numbers) => 
 // Count by Sign (-1, 0 1)
 const countSign = _.countBy(numbers, Math.sign);
 // _.countBy return object, of counted '1': 2, '0': 1, '-1': 2 
 
 // Print them in orders
 const printOrder = [1, -1, 0];
 printOrder.forEach(sign => 
 console.log((countSign[sign] / numbers.length).toFixed(6));
 );


const testArr = [1,1,0,-1,-1];
plusMinus(testArr);

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.11/lodash.min.js"></script>

const plusMinus = arr => arr
 .reduce((res, curr) => ++res[!curr ? 2 : curr < 0 ? 1 : 0] && res, [0, 0, 0])
 .forEach(i => console.log((i / arr.length).toFixed(6)));

plusMinus([1, 1, 0, -1, -1]);