CBSE NET January 2017 PAPER II
DATA STRUCTURE
Q. The seven elements A, B, C, D, E, F and G are pushed onto a stack in reverse order, i.e., starting from G. The stack is popped five times and each element is inserted into a queue. Two elements are deleted from the queue and pushed back onto the stack. Now, one element is popped from the stack. The popped item is ……………….
(A) A
(B) B
(C) F
(D) G
Ans :- (B)
Explanation:-
Push GFEDCBA
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A
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B
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C
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D
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E
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F
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G
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Pop 5 times and pop elements are queued EDCBA
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F
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G
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2 elements deleted from queue, EDC, and pop in to stack
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B
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A
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F
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G
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1 element pop from stack. That is B
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A
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F
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G
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