This is not your problem:
20:47:03 INFO]: Looking for orphaned versions to clean up...
[20:47:03 FATAL]: Fatal error launching game. Report this to http://bugs.mojang.com please!
java.io.FileNotFoundException: File 'C:\Users\hp\AppData\Roaming\.minecraft\assets\indexes\legacy.json' does not exist
at org.apache.commons.io.FileUtils.openInputStream(FileUtils.java:299) ~[launcher.jar:1.6.11]
at org.apache.commons.io.FileUtils.readFileToString(FileUtils.java:1711) ~[launcher.jar:1.6.11]
at net.minecraft.launcher.Launcher.cleanupOrphanedAssets(Launcher.java:253) ~[launcher.jar:1.6.11]
at net.minecraft.launcher.Launcher.performCleanups(Launcher.java:495) ~[launcher.jar:1.6.11]
This message is alarming but meaningless in this context where it is happening with "performCleanups" in the stack trace. This is the cleaning step that happens after the game has exited, and unless you have ever launched a "legacy" version of minecraft before your launcher will not have downloaded the legacy.json file.
Just one of the many instances where a little effort on Mojang's part to clean up their code would make everyone's life simpler.
This is your problem, and not very informative.
[20:47:08 ERROR]: Game ended with bad state (exit code 1)
Post the game output log.