function find_FirstNotRepeatedChar(str) { var arra1 = str.split(''); var result = ''; var ctr = 0; for (var x = 0; x < arra1.length; x++) { ctr = 0; for (var y = 0; y < arra1.length; y++) { if (arra1[x] === arra1[y]) { ctr+= 1; } } if (ctr < 2) { result = arra1[x]; break; } } return result; } console.log(find_FirstNotRepeatedChar('abacddbec'));