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I haven't checked all lines of your code, but just line relevant to bold one (the problematic line).
The error message you might have gotten is quite self explanatory. All you are doing is declaring a Runnable reference without initializing it, then initializing it in for loop, and outside the loop, you are using same reference (whose initialization in for loop is out of scope now) to create a new Thread object.
Please put all your relevant logic in proper loops and it should work (at least syntactically).