빈번한 Range.getValue() 및 Range.setValue() 호출로 인해 발생하는 과도한 처리 시간을 줄이기 위해 Google Apps 스크립트를 최적화하려면 어떻게 해야 합니까?

function format() {
  const SS = SpreadsheetApp.getActiveSpreadsheet();
  const SHEET = SS.getActiveSheet();
  const LAST_ROW = SHEET.getRange('A:A').getLastRow();
  let row, range1, cellValue, offset1, offset2, offset3;

  // Loop through all cells in column A
  for (row = 0; row < LAST_ROW; row++) {
    range1 = SHEET.getRange(row + 1, 1);

    // If cell substring is a number, skip it as substring cannot process numbers
    cellValue = range1.getValue();
    if (typeof cellValue === 'number') continue;

    // Check for the state code prefix "-"
    const DASH = cellValue.substring(0, 1);

    // Get neighboring cells
    offset1 = range1.offset(1, 0).getValue();
    offset2 = range1.offset(2, 0).getValue();
    offset3 = range1.offset(3, 0).getValue();

    // Handle state code "-"
    if (DASH === '-') {
      // Merge cells 1 and 2 and write "Order complete" in cell 2
      range1.offset(1, 0).setValue(offset1 + ' ' + offset2);
      range1.offset(2, 0).setValue('Order complete');
    }

    // Insert cell if offset 3 is not blank
    if (DASH === '-' && offset3 !== '') {
      // Select cells from 3 rows down
      SHEET.getRange(row + 1, 1, LAST_ROW)
        .offset(3, 0)
        .moveTo(range1.offset(4, 0));
    }
  }
}