I need to count the occurrence of characters in a given string and print out the unique characters and the number of how many times they appeared. So, for example, if I receive a string of 'HELLO' it should print out:
H: 1, E: 1, L: 2, O: 1
This is a much-simplified version of a problem, but the answer should put me in the right direction. How can I approach this problem?
Thank you in advance.
This is more or less what it should look like in order to make it easier it prints it in JSON you can already convert it to String yourself if you want.
function count_occurrence(text = "") {
const array_from_text = text.split("");
const result = {};
Array.from(new Set(array_from_text)).forEach(word => {
const { length } = array_from_text.filter(w => w === word);
result[word] = length;
});
return result;
};
const occurences = count_occurence("HELLO");
console.log(occurences); // {H: 1, E: 1, L: 2, O: 1}
const countChars = (str) => {
const charCount = {} ;
for (const c of [...str]) {
charCount[c] = (charCount[c] || 0) + 1 ;
}
return charCount ;
}
console.log(countChars('HELLO')) ; // {H: 1, E: 1, L: 2, O: 1}
You could use Array.reduce() to get a count of each occurrence in the input word.
We convert the word to an array using the ... operator, then .reduce() to create an object with a property for each unique letter in the word.
const input = 'HELLO';
const result = [...input].reduce((acc, chr) => {
acc[chr] = (acc[chr] || 0) + 1;
return acc;
}, {});
console.log('Result:', result).as-console-wrapper { max-height: 100% !important; }