There are many variants of Rudrata’s problem, depending on whether the graph is undirected or directed, and whether a cycle or path is sought. Reduce the DIRECTED RUDRATA PATH problem to each of the following.(a)The (undirected) RUDRATA PATH problem.(b) The undirected RUDRATA PATH problem, which is just like RUDRATA PATH except that the endpoints of the path are specified in the input.

Short Answer

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2. Enumerating the source and destination solves the given problem.

Step by step solution

01

Explain the RUDTATA PATH problem

Consider a directed or undirected graph, In which there exists a path that visits each vertex exactly once. The path is known as RUDRATA PATH.

02

Reduce undirected RUDTATA PATH problem

Consider the directed graph G, in which each vertex v is categorized into new and old vertices i+o. In-degree vertices are represented as i and the out-degree vertices are represented as o. Consider that every directed edge is connected to the vertex that is transformed intoi+onew undirected edge of the vertex.

Assume that the vertex connected to the incoming edges is called the incoming vertex and the vertex connected to the outgoing edges is called the outgoing vertex. Connect each incoming vertex to undirected edges.

Thus, the graph G is transformed into G'. Consider the following example,

Therefore, the undirected graph is reduced to RUDATA PATH.

03

The undirected RUDRATA (s,t)− PATH problem.

Consider the directed graph G, in which each vertex is categorized into new and old vertices . In-degree vertices are represented as and the out-degree vertices are represented as . Consider that every directed edge is connected to the vertex that is transformed into new undirected edge of the vertex.

Based on the above graph information, enumerate the path as . Consider the vertex source as , and the vertex that ends the cycle is t.

Therefore, enumerating the source and destination solves the given problem.

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Most popular questions from this chapter

Question: 0.1. In each of the following situations, indicate whether f=O(g),orf=Ω(g),or both (in which case f=(g))

How long does the recursive multiplication algorithm (page 25) take to multiply an n -bit number by an m -bit number? Justify your answer.

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We start by writing the equations F1=F1 and F2=F0+F1 in matrix notation:


role="math" localid="1659767046297" (F1F2)=(0111).(F0F1).

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F2F3=(0111).(F1F2)=(0111)2.(F0F1)

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c. Show that all intermediate results of fib3 are O(n) bits long.


d. Let M(n)be the running time of an algorithm for multiplying n-bit numbers, and assume that M(n)=O(n2) (the school method for multiplication, recalled in Chapter 1, achieves this). Prove that the running time of fib3 is O(M(n)logn).


e. Can you prove that the running time of fib3 is O(M(n))? Assume M(n)=Θ(na)for some 1a2. (Hint: The lengths of the numbers being multiplied get doubled with every squaring.)


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role="math" localid="1659768125292" Fn=15(1+52)n15(152)n.

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