JSFiddle - React, Tailwind, and code Playground
JavaScript
/**
* trimSymbols
* @param {string} string
* @param {number} size
* @returns {string}
*/
function trimSymbols (string, size) {
const firstSlice = string.slice(0, size);
const rest = [...string.slice(size)];
return rest.reduce((accum, item) => {
if (!accum.endsWith(item.repeat(size))) {
accum += item;
}
return accum;
}, firstSlice);
}
console.log(trimSymbols('xxxaaaaab', 3)); // xxaa