# How to get all maximum frequency characters in string?

I have a string and I want to retrieve all the characters with maximum occurring frequency. I have created a function that returns a single maximum frequency character in the string. But how to modify it in such a way that it returns all the characters with maximum occurring frequency in form or array or string.

```  const str = "helloo"

function findMaxChar(str) {
let obj = {}
let maxVal = 1
let val

for (let i = 0; i < str.length; i++) {
if (str[i] !== ' ') {
if (obj.hasOwnProperty(str[i])) {
obj[str[i]] = obj[str[i]] + 1
}
else {
obj[str[i]] = 1
}
}}
for (const item in obj) {
if (obj[item] > maxVal) {
maxVal = obj[item]
val = item
}
}
return val
}

Desired output = [l, o]   // since both l and o has maximum occuring frequency
```

Maybe create a loop that finds the highest number of occurrences in a string, and then in the next loop check what characters appear that many times.

```const str = "helloo"

function findMaxChar(str) {
let obj = {}
let maxVal = 0
let valArr = [];

for (let i = 0; i < str.length; i++) {
if (str[i] !== ' ') {
if (obj.hasOwnProperty(str[i])) {
obj[str[i]] = obj[str[i]] + 1
}
else {
obj[str[i]] = 1
}
}}

for (const item in obj) {
if (obj[item] >= maxVal) {
maxVal = obj[item];
}
}

for (const item in obj) {
if (obj[item] === maxVal) {
valArr.push(item)
}
}

return valArr.length > 1 ? valArr : valArr.join();

}

console.log(findMaxChar(str))```
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