Google Apps Script to add links to google Spreadsheet adds 5000+ rows and i dont understand why? - for-loop

Question

Pretty self explanatory title, im trying to do a script where it takes the number on a column and uses that to search a list of files from google drive and then insert a link to that file.
HOWEVER, every time it inserts that link it also creates like 5000+ empty rows? why would this be?
The purpose is to take a number from a certain column, then look on google drive for the file that matches (at least partially) with that first number, then we should generate a link for that file and insert that link into another column, next to the number.
function CopiarResos() {
let ass = SpreadsheetApp.getActiveSpreadsheet();
let maxRows = ass.getSheetByName('set_de_datos_unificado').getMaxRows();
let columnaResos = ass.getSheetByName('set_de_datos_unificado').getSheetValues(2,2,maxRows,1);
let columnaLinks = ass.getSheetByName('set_de_datos_unificado').getSheetValues(2,53,maxRows,1);
let folder = DriveApp.getFolderById('1FJiet6tVgWXtM91Y7mmhgxDL2iYFm1VE'); // I change the folder ID here
let list = [];
let idList = [];
let files = folder.getFiles();
let match = '';
while (files.hasNext()){
file = files.next();
list.push(file.getName().toString());
idList.push(file.getId().toString());
}
console.log(list);
console.log(idList);
/*
let match = list.find(element => {
if (element.includes(substring)) {
return true;
}
});
*/
for (let i = 0; i in columnaResos; i++){
if(columnaLinks[i] == ""){
let substring = columnaResos[i];
match = list.find(element => {
if (element.includes(substring)) {
let idString = idList[i];
let insertStr = "https://drive.google.com/file/d/" + idString +"view";
let cellInsert = ass.getSheetByName('set_de_datos_unificado').getRange([i]+2,53);
cellInsert.setValue(insertStr);
return true;
}
});
}
};
}

Answer 1

getMaxRows() returns the number of rows that has the sheet (scroll down to the very bottom). You might delete the blank rows below your data or use getLastRow() instead.
References
https://developers.google.com/apps-script/reference/spreadsheet/sheet#getmaxrows
https://developers.google.com/apps-script/reference/spreadsheet/sheet#getlastrow

Answer 2

So, apart from all the thing wasnt written right turns out i was missing a bunch of lines! Mostly i was trying to get a fileid from an array even tho the indexes were completely unrelated (eg: trying to get list[300] instead of doing indexOf(match)
function copiarResos() {
let ass = SpreadsheetApp.getActiveSpreadsheet();
let maxRows = ass.getSheetByName('set_de_datos_unificado').getLastRow();
let columnaResos = ass.getSheetByName('set_de_datos_unificado').getSheetValues(2,2,maxRows,1);
let columnaLinks = ass.getSheetByName('set_de_datos_unificado').getSheetValues(2,53,maxRows,1);
let folder = DriveApp.getFolderById('1FJiet6tVgWXtM91Y7mmhgxDL2iYFm1VE'); // I change the folder ID here
let list = [];
let files = folder.getFiles();
let match = '';
while (files.hasNext()){
file = files.next();
list.push(file.getName().toString(), file.getId().toString());
}
console.log(list);
console.log(columnaLinks)
for (let i = 0; i in columnaResos; i++){
if(columnaLinks[i] == ''){
let substring = columnaResos[i];
match = list.find(element => {
if (element.includes(substring)) {
return true;
}
});
console.log(match);
matchId = list.indexOf(match);
if(matchId !== 0){
console.log(match + " id es" + matchId);
let idString = list[matchId+1];
console.log(idString)
let insertStr = "https://drive.google.com/file/d/" + idString +"/view?usp=sharing";
let cellInsert = ass.getSheetByName('set_de_datos_unificado').getRange(i+2 ,53);
cellInsert.setValue(insertStr);
}
}
match = ''
};
}