# Recent posts in Theory of Computation

1
Queue is FIFO and W is arriving first. Now, when P is blocked it should go behind W in queue.
2
2, 3 and 4 are possible for implementing inverted list. Basically we need an indexed access to the file (as in hashing) but this might not be there in a simple sequential file. http://orion.lcg.ufrj.br/Dr.Dobbs/books/book5/chap03.htm
3
Yes. Because both are ADD instructions and before the write to R2 in the second instruction the Read for I1 would be completed. But this assumes I1 is not waiting for any other operand- no other data dependencies.
4
It is true that the counting starts from 0, so the 29th sector is actually the 30th sector. Or is it?! Notice that although the counting begins with 0, the starting sector is labelled the 0th sector, and not the first. So, to reach the sector marked by the address <0, 0, 3>, we need to goto ... 0th sector <0,0,1> = 1st sector <0,0,2> = 2nd sector <0,0,3> = 3rd sector ... <0,0,29> = 29th sector.
6
The truth table ${\begin{array}{|c|c|c|}\hline \textbf{X}& \textbf{Y}& \textbf{(X,Y)} \\\hline 0& 0& 0 \\ \hline 0& 1&0\\ \hline 1& 0& 1 \\\hline 1& 1& 1 \\\hline \end{array}}$ represents the Boolean function $X$ $X + Y$ $X \oplus Y$ $Y$