ok, first
Qt Code:
  1. QString pepelu = lineaHora.left(6)+lineaHora.right(5);
  2. QDateTime dias = QDateTime::fromString(pepelu,"yyMMddhhmm");
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6+5 = 11. yyMMddhhmm == 10! I think.

Then in the while loop you set the result every time on the same label. And I guess your last line which is precessed in an empty line. So the label will show nothing.