CLRS refers to the textbook "Introduction to Algorithms" by Thomas H. Cormen, Charles E. Leiserson, Ronald R. Rivest, and Clifford Stein. It is a standard textbook in algorithms and data structures.
Questions tagged [clrs]
170 questions
0
votes
2 answers
Cannot understand CLRS Problem 4-2 case 2
The question:
4-2 Parameter-passing costs
Throughout this book, we assume that parameter passing during procedure calls takes constant time, even if an N-element array is being passed. This assumption is valid in most systems because a pointer to…
Xazy
- 9
- 3
0
votes
2 answers
Why does the "for" loop execute one more time than the body of the loop?
In the book Introduction to Algorithms, there is a line under the heading Analysis of Insertion Sort that reads:
"When a for or while loop exits in the usual way (i.e., due to the test in the loop header), the test is executed one time more than…
Shiladitya Mukherjee
- 65
- 1
- 7
0
votes
1 answer
Solving Negative coefficients in linear program
I am trying to solve a assignment problem using linear programming.
I am using the simplex algorithm mentioned in CLRS.
Consider the below example:
--(1/1)--->|a|---(10/1)------>|d|----------->
| | ^ …
Abis
- 155
- 8
0
votes
1 answer
Explanation to Rabin Karp from CLRS
I've been reading the Rabin Karp algorithm from Introduction To Algorithms. Everything makes sense except the following.
In general, with a d-ary alphabet {0, 1, . . ., d - 1}, we choose q so
that dq fits within a computer word
I don't understand…
Rajat Saxena
- 3,834
- 5
- 45
- 63
0
votes
1 answer
Use Floyd-Warshall algorithm to find negative-weight circles
To judge whether a graph contains negative-circles, after running the Floyd-Warshall algorithm, can I deal with the problem only by scanning the diagonal elements of the matrix to find whether it has negative elements. I dont't know how to prove…
NiaBie
- 55
- 1
- 9
0
votes
1 answer
Result calculation in rod cutting
I am learning the rod cutting algorithm from CLRS book.
I believe I understand the logic and my below solution was accepted on this OJ.
#include
#include
using namespace std;
int prices[101];
int result[101];
int…
PM_ME_PUZZLES
- 11
- 3
0
votes
1 answer
implementing priority queues and heaps
I am trying to implement a min priority queue using a binary min heap based on the description from "Introduction to Algorithms, Third Edition" and have a couple of questions.
The book says that we often need to store a handle (pointer or integer)…
James Miller
- 25
- 1
- 4
0
votes
1 answer
Confused about a convention in pseudocode from Introduction to Algorithms
I have the follwoing convention in pseudocode, from the Introduction to Algorithims textbook:
Parameters are passed to a procedure by value: the called procedure receives
its own copy of the parameters, and if it assigns a value to a parameter,…
Jake Wright
- 373
- 1
- 8
0
votes
1 answer
Worst case in Max-Heapify - Why can you get 2n/3?
I have figured out how to get 2n/3 from the following question:
Worst case in Max-Heapify - How do you get 2n/3?
"In CLRS, third Edition, on page 155, it is given that in MAX-HEAPIFY:
'The children’s subtrees each have size at most 2n/3—the worst…
fatpanda2049
- 483
- 1
- 4
- 9
0
votes
1 answer
Modular arithmatic in Rabin-karp algorithm
I am studying Rabin-karp algotithm for string matching from CLRS in which modular arithmetic is used for hashing which i haven't studied so what I don't understand is that how does (7 – 3·3)·10 + 2 (mod 13) evaluate to 8 (mod 13)
user7845429
- 103
- 1
- 8
0
votes
0 answers
Python: AND operator in IF statement
It is a heap sort.
def Parent(i):
return i / 2
def Left(i):
return 2 * i
def Right(i):
return 2 * i + 1
def MAX_HEAPIFY(A, i): # A.heapSize == A[0]
l = Left(i)
r = Right(i)
Here is the problem.
if l <= A[0] and A[l] >…
Belent
- 1
0
votes
1 answer
Regarding subsequences - CLRS
I am reading chapter 15 from CLRS and came across this definition of a subsequence:
A subsequence of a given sequence is just the given sequence with zero
or more elements left out.
Later it is said that:
Each subsequence of X corresponds to a…
babon
- 3,615
- 2
- 20
- 20
0
votes
1 answer
solving the recurrance by the method of substitution
While learning the algorithms and referring to CLRS, I came across a problem
T(n) = T(n-a) + T(a) + cn ; a >= 1 and c > 0
it is Big-theta(n^2), can be easily proved by recursion tree method
I can solve it by the method of recursion tree.
While…
Adorn
- 1,403
- 1
- 23
- 46
0
votes
1 answer
Red Black Tree in C
I am trying to implement red black tree in C. For reference I am using CLRS.
But when I run the code I am getting "Segmentation fault (core dumped)" error message.
I can't figure out what's wrong in my code so, could anyone tell me what's wrong in…
Rahul Kumar
- 29
- 8
0
votes
1 answer
Understanding BELLMAN-FORD algorithm from CLRS
Consider this simple graph:
S -> A -> B -> C
In CLRS, the authors have implemented a loop which goes for |V|-1.
But according to path-relaxation property a simple path P can be < s,a,b,c >.
Using the path-relaxation property we are going to relax…
Rajat Saxena
- 3,834
- 5
- 45
- 63