Simultaneous resource bounded complexity classes for nondeterministic single worktape off-line Turing machines are considered such as time-space bounded classes, denoted by NTISP1(T, S), reversal-space bounded classes, denoted by NRESP1(R, S), and time-reversal bounded classes, denoted by NTIRE1(T, R). It is shown that NRESP1(R(n), S(n)) contains NTISP1(S(n), R(n)) and is contained in NTISP1(R(n) S(n)n2 log n, R(n) log n). The following corollaries follow: (1) the affirmative solution to the nondeterministic single worktape version of the NC = ? SC problem, NTIRE1(poly, polylog) = NTISP1(poly, polylog), and (2) a reversal-space trade-off, NRESP1(polylog, poly) = NRESP1(poly, polylog).
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