String.prototype.replaceAll = function(search, replacement) {
    var target = this;
    return target.replace(new RegExp(search, 'g'), replacement);
};


var str = `1G;5W|2L;4V|1P;4J|1Q;2H;3O;4E|2S;5F
4C 5Y   1G 3D 4X   3I   3T 5K   2H
1R 2Q 5E   1F 3S 4C 5Y     1M 3I 5B   5K
2P 4T   4O 5E   1F 3S 5Y   1G   1M 4V
1B 3L 4I 5V   1K 4T 5J   1R  2A 3S 4C  1G 4X 5W
1W 4D   4I 5V   3N 4T 5J   4O   1F
1Y 5C   2G 3U 5X   5V   3N 4T 5J   1R 2Q
3Q 5O   1Y   1W 2G 4D 5X     2P 4T
1J 2K   1E 4H 5O   2F 4S 5C   1W 3U 5X   2M 3L 5V
2B 4L   2K 3P   2R 3Q 4H 5O   1Y 5C   2G 5X
1X 2W 3G 5D   1V 2B 3M   5T   1E 4H 5O   2F 5C
5S   1X 2W 3G 4U   2B 3M  1J 2K   4H 5K
1O 2E 4Q 5H   2Y   5D   2B 4L 5I   4N 5T
1T 2J 4P   1O 3R 5H   2Y 4A 5S   2W 4U   1V 2B 5I
4M   5N   1O   1C 5S
2X   5L   1T 2J 5N   4Q 5H   4A
1S 2C 3Y 4F 5A   1D 2X   1I   3K 4P 5N   3R 4Q
2O 3E   1S 2C      1I 4M   1T
1N 2T 3J 5P   2O   1S 5A   2X 5U   4M
1L 3V 5M   1N   1H 2O 3E   1S 2C 5F   1D 2X
1U 2D 5G   3V 4B 5M   1N 2T   2O 5Q   1S 3Y 5A
1A 3C 4Y 5F   1U 3X   1L 2I 3V 4B 5M   2T   1H 2O 3E 4R
1Q 3O 4E   5F   3X   1L 2I 4B 5M   1N 5P
5K   5R   1A 3C 4Y 5F   2D 4W   2I 3V 4B
1M 3I 4V   1P   3O 4E 5R   1A 2S 5F   4W`

var notation = str.replaceAll("   ", "|").replaceAll("  ", "|").replaceAll(" ", ";");
console.log(notation);

var row = 1;
var base = 0;
var temp = "";
for (var i = 0; i < notation.length; i++) {
  var charAt = notation.charAt(i);
  if (temp.includes("\n")) { temp = ""; base = 0; row++; }
  if (charAt == "|") { temp = ""; base+=5;}
  else if (charAt == ";") temp = "";
  else temp += charAt;
  if (temp.length == 2) {
    console.log(row, base+parseInt(temp.charAt(0)), temp);
    getSquare(row, base+parseInt(temp.charAt(0))).value = temp.charAt(1).charCodeAt(0) - 64;

  }
}

function getNextColumn(current) {
  return current <= 5 ? 6 : current <= 10 ? 11 : current <= 15 ? 16 : current <= 20 ? 21 : current <= 20 ? 21 : -1;
}


function getSquare(trow, tcolumn) {
var row = 1;
var column = 1;
var result;
document.querySelectorAll("#gridArea p *").forEach(element => {
  if (element.nodeName == "BR") {
    row++; column = 1;
  } else {
    if (row == trow && tcolumn == column) result = element;
    column++;
  }
});
return result;
}