Remove duplicates based on one column and keep latest entry in google sheets

Question

I was working on some automation and wanted to remove the duplicate rows in my google sheet by comparing it on basis of 3rd column. I found one code which is working flawlessly but it does not remove the old entry in sheet, it removes the latest one. I wanted to keep the latest one from the duplicates.

This is the code which I found for appscript by Cooper:

function removeDuplicates() {
  var sh=SpreadsheetApp.getActiveSheet();
  var dt=sh.getDataRange().getValues();
  var uA=[];
  var d=0;
  for(var i=0;i<dt.length;i++) {
    if(uA.indexOf(dt[i][2])==-1) {
      uA.push(dt[i][2]);
    }else{
      sh.deleteRow(i+1-d++);
    }
  }
}

Can anyone help me with the code which does the same work "removing duplicate rows (Keeps latest entry removes the old entry) based on column" ?

Answer 1

From I wanted to keep the latest one from the duplicates., when the latest one is the last row, in your script, how about the following modification?

Modified script:

function removeDuplicates() {
  var sh = SpreadsheetApp.getActiveSheet();
  var dt = sh.getDataRange().getValues();
  var uA = [];
  for (var i = dt.length - 1; i >= 0; i--) {
    if (uA.indexOf(dt[i][2]) == -1) {
      uA.push(dt[i][2]);
    } else {
      sh.deleteRow(i + 1);
    }
  }
}