Observe the following question carefully and answer accordingly.


  • 3
    $\begingroup$ is it really puzzle , or you just pressed randomly on keyboard.as there are many A's U's and S's $\endgroup$ – Amruth A Jul 29 '16 at 10:16
  • 4
    $\begingroup$ stackoverflow.com/questions/22413868/… $\endgroup$ – smriti Jul 29 '16 at 10:18
  • $\begingroup$ is this helpful? $\endgroup$ – smriti Jul 29 '16 at 10:19
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    $\begingroup$ If you use this tool to convert the string it's literally just a 15x15 red image. I don't know if it's reliable, though. $\endgroup$ – user14478 Jul 29 '16 at 10:19
  • $\begingroup$ @smriti Yes, go ahead! $\endgroup$ – Hitesh Dholaria Jul 29 '16 at 10:32

The answer is



This is a base64 encoded binary file that contains two png files. When viewing this in a normal viewer, it will only read the first png file, which is a red square. When the two files are shown on top of each other by a non-conforming (as in: does not follow the specification) PNG viewer it will show the green square under this red square.

as shown here:

enter image description here

  • $\begingroup$ @Samurai8 Quite close to the answer but not the correct answer yet! $\endgroup$ – Hitesh Dholaria Jul 29 '16 at 11:00
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    $\begingroup$ I am clueless as to what you expect more as an answer. This question depends on a non-conformant image viewer. Simply overlaying them does not work: jsfiddle.net/qzutx783 . There are no text blocks in the image data. There is a CR3 sequence inside the IDAT block that is quite different from the other image. I can't find any documentation on that whatsoever though. $\endgroup$ – Sumurai8 Jul 29 '16 at 12:49
  • $\begingroup$ The L is Vladimir Lenin, of course. He's buried in the Red Square. :) $\endgroup$ – M Oehm Jul 31 '16 at 15:40
  • $\begingroup$ That... well, that sounds like it could be an answer. $\endgroup$ – Sumurai8 Jul 31 '16 at 18:22

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