# Greedy Technique

 Question 1
Consider the string abbccddeee. Each letter in the string must be assigned a binary code satisfying the following properties:

For any two letters, the code assigned to one letter must not be a prefix of the code assigned to the other letter.
For any two letters of the same frequency, the letter which occurs earlier in the dictionary order is assigned a code whose length is at most the length of the code assigned to the other letter.

Among the set of all binary code assignments which satisfy the above two properties, what is the minimum length of the encoded string?
 A 21 B 23 C 25 D 30
GATE CSE 2021 SET-2   Algorithm
Question 1 Explanation:
 Question 2
Define $R_n$ to be the maximum amount earned by cutting a rod of length n meters into one or more pieces of integer length and selling them. For $i > 0$, let $p[i]$ denote the selling price of a rod whose length is $i$ meters. Consider the array of prices:

$\text{p}[1]=1,\text{p}[2]=5,\text{p}[3]=8,\text{p}[4]=9,\text{p}[5]=10,\text{p}[6]=17,\text{p}[7]=18$

which of the following statements is/are correct about $R_7$?
[MSQ]
 A $R_7=18$ B $R_7=19$ C $R_7$ is achieved by three different solutions. D $R_7$ cannot be achieved by a solution consisting of three pieces.
GATE CSE 2021 SET-1   Algorithm
Question 2 Explanation:
 Question 3
Huffman tree is constructed for the following data :{A,B,C,D,E} with frequency {0.17, 0.11, 0.24, 0.33 and 0.15} respectively. 100 00 01101 is decoded as
ISRO CSE 2020   Algorithm
Question 3 Explanation:
 Question 4
Consider the weights and values of items listed below. Note that there is only one unit of each item.

The task is to pick a subset of these items such that their total weight is no more than 11 Kgs and their total value is maximized. Moreover, no item may be split. The total value of items picked by an optimal algorithm is denoted by $V_{opt}$. A greedy algorithm sorts the items by their value-to-weight ratios in descending order and packs them greedily, starting from the first item in the ordered list. The total value of items picked by the greedy algorithm is denoted by $V_{greedy}$.
The value of $V_{opt}$-$V_{greedy}$ is ____________.
 A 36 B 40 C 16 D 0
GATE CSE 2018   Algorithm
Question 4 Explanation:
 Question 5
A message is made up entirely of characters from the set X= {P,Q,R,S,T}. The table of probabilities for each of the characters is shown below:

If a message of 100 characters over X is encoded using Huffman coding, then the expected length of the encoded message in bits is_____
 A 225 B 115 C 275 D 315
GATE CSE 2017 SET-2   Algorithm
Question 5 Explanation:
 Question 6
Consider the following table:

Match the algorithms to the design paradigms they are based on.
 A P-(ii), Q-(iii),R-(i) B P-(iii), Q-(i), R-(ii) C P-(ii), Q-(i), R-(iii) D P-(i), Q-(ii), R-(iii)
GATE CSE 2017 SET-1   Algorithm
Question 6 Explanation:
 Question 7
Suppose P, Q, R, S, T are sorted sequences having lengths 20, 24, 30, 35, 50 respectively. They are to be merged into a single sequence by merging together two sequences at a time. The number of comparisons that will be needed in the worst case by the optimal algorithm for doing this is ____.
 A 362 B 358 C 456 D 320
GATE CSE 2014 SET-2   Algorithm
Question 7 Explanation:
 Question 8
Consider a job scheduling problem with 4 jobs $J_1, J_2, J_3$ and $J_4$ with corresponding deadlines: $(d_1, d_2, d_3, d_4) = (4, 2, 4, 2)$. Which of the following is not a feasible schedule without violating any job schedule?
 A $J_2, J_4, J_1, J_3$ B $J_4, J_1, J_2, J_3$ C $J_4, J_2, J_1, J_3$ D $J_4, J_2, J_3, J_1$
ISRO CSE 2007   Algorithm
Question 8 Explanation:
 Question 9
Consider n jobs $J_1, J_2 \dots J_n$ such that job $J_i$ has execution time $t_i$ and a non-negative integer weight $w_i$. The weighted mean completion time of the jobs is defined to be $\frac{\sum_{i=1}^{n}w_iT_i}{\sum_{i=1}^{n}w_i}$, where $T_i$ is the completion time of job $J_i$. Assuming that there is only one processor available, in what order must the jobs be executed in order to minimize the weighted mean completion time of the jobs?
 A Non-decreasing order of $t_i$ B Non-increasing order of $w_i$ C Non-increasing order of $w_it_i$ D Non-increasing order of $w_i/t_i$
GATE IT 2007   Algorithm
Question 9 Explanation:
 Question 10
Suppose the letters a, b, c, d, e, f have probabilities 1/2, 1/4, 1/8, 1/16, 1/32, 1/32 respectively.

What is the average length of the Huffman code for the letters a,b,c,d,e,f?
 A 3 B 2.1875 C 2.25 D 1.9375
GATE CSE 2007   Algorithm
Question 10 Explanation:
There are 10 questions to complete.

### 1 thought on “Greedy Technique”

1. I have a request to the site owner that please don’t upload the options for Numerical Type Question[NAT], just make it as correct or wrong, if possible.