     function uintToString(uint _uint) public pure returns (string str) {
         uint len = 0;
         uint m = _uint + 0;
         while (m != 0) {
             len++;
             m /= 10;
         }
         bytes memory b = new bytes(len);
         uint i = len - 1;
         while (_uint != 0) {
             uint remainder = _uint % 10;
             _uint = _uint / 10;
             b[i--] = byte(48 + remainder);
         }
         str = string(b);
     }