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Multi Stack Machine

A two push down stack machine,a 2PDA is like a PDA except that it has two push down stacks STACK1 and STACK2 . When we wish to push a character x into a stack,we have to specify which stack,either PUSH1 x or PUSH2 x. When we POP a STACK for the purpose of branching we must specify which STACK,either POP1 and POP2 (Read character from read only input tape).

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