Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles on Trending Technologies
Technical articles with clear explanations and examples
Find maximum in stack in O(1) without using additional stack in C++
Suppose we want to make a stack that can store the maximum element in the stack. And we can get it in O(1) time. The constraint is that, it should not use any additional space, so O(1) extra space.We can make one user-defined stack, that will store the max value, when one operation is performed, like pop or peek, then the max will be returned. For peek operation, return the maximum of stack top and the max element, for pop operation, when the top element is larger, then print it and update max as 2*max – top_element. otherwise return top_element. ...
Read MoreDefine and Call a Subroutine in Perl
The general form of a subroutine definition in Perl programming language is as follows −sub subroutine_name { body of the subroutine }The typical way of calling that Perl subroutine is as follows −subroutine_name( list of arguments );In versions of Perl before 5.0, the syntax for calling subroutines was slightly different as shown below. This still works in the newest versions of Perl, but it is not recommended since it bypasses the subroutine prototypes.&subroutine_name( list of arguments );Let's have a look into the following example, which defines a simple function and then call it. Because Perl compiles your program before ...
Read MorePassing Arguments to a Subroutine in Perl
You can pass various arguments to a Perl subroutine like you do in any other programming language and they can be accessed inside the function using the special array @_. Thus the first argument to the function is in $_[0], the second is in $_[1], and so on.You can pass arrays and hashes as arguments like any scalar but passing more than one array or hash normally causes them to lose their separate identities. So we will use references ( explained in the next chapter ) to pass an array or hash.Let's try the following example, which takes a list ...
Read MoreFind minimum number of currency notes and values that sum to given amount in C++
Suppose we have such amount, and we have to find the minimum number of notes of different denominations, that sum up to the given amount. Start from highest denomination notes, try to find as many notes possible for given amount. Here the assumption is that we have infinite amount of {2000, 500, 200, 100, 50, 20, 10, 5, 2, 1}. So if the amount is say 800, then notes will be 500, 200, 100.Here we will use the greedy approach to solve this problem.Example#include using namespace std; void countNotes(int amount) { int notes[10] = { 2000, 500, 200, 100, ...
Read MorePassing Lists to Subroutines in Perl
Because the @_ variable is an array in Perl, it can be used to supply lists to a subroutine. However, because of the way in which Perl accepts and parses lists and arrays, it can be difficult to extract the individual elements from @_. If you have to pass a list along with other scalar arguments, then make list as the last argument as shown below −Example#!/usr/bin/perl # Function definition sub PrintList { my @list = @_; print "Given list is @list"; } $a = 10; @b = (1, 2, 3, 4); # Function call with list parameter ...
Read MoreFind profession in a special family in C++
Consider there is a special family of doctors and engineers. There are some rules, these are like below −Everybody has two childrenFirst child of an engineer is an engineer, second child is doctorFirst child of a doctor is a doctor, second child is an engineerAll generations of doctors and engineers starts with engineerSo if we want to get result for level 4 and pos 2, then result will be DoctorThe idea is simple. Profession of a person depends on following two.Profession of the parent.Position of node: When the position of a node is odd, then its profession is same as ...
Read MorePassing Hashes to Subroutines in Perl
When you supply a hash to a Perl subroutine or operator that accepts a list, then the hash is automatically translated into a list of key/value pairs. For example −Example#!/usr/bin/perl # Function definition sub PrintHash { my (%hash) = @_; foreach my $key ( keys %hash ) { my $value = $hash{$key}; print "$key : $value"; } } %hash = ('name' => 'Tom', 'age' => 19); # Function call with hash parameter PrintHash(%hash);OutputWhen the above program is executed, it produces the following result −name : Tom age : 19
Read MoreFind relative complement of two sorted arrays in C++
Suppose we have two sorted arrays arr1 and arr2, there sizes are m and n respectively. We have to find relative complement of two arrays. It means that we need to find all those elements which are present in arr1, but not in arr2. So if the arrays are like A = [3, 6, 10, 12, 15], and B = [1, 3, 5, 10, 16], then result will be [6, 12, 15]To solve this, we can use the set_difference function. As the problem is basically set difference operation.Example#include #include #include using namespace std; int main() { int first[] = ...
Read MoreReturning Value from a Subroutine in Perl
You can return a value from Perl subroutine as you do in any other programming language. If you are not returning a value from a subroutine then whatever calculation is last performed in a subroutine is automatically also the return value.You can return arrays and hashes from the subroutine like any scalar but returning more than one array or hash normally causes them to lose their separate identities. So we will use references ( explained in the next chapter ) to return an array or hash from a function.ExampleLet's try the following example, which takes a list of numbers and ...
Read MoreFind sum of all nodes of the given perfect binary tree in C++
Suppose we have a positive integer L, which represents the number of levels in a perfect binary tree. The leaf nodes in this perfect binary tree are numbered starting from 1 to n. Where the n is number of leaf nodes. The parent node is the sum of children. Our task is to write a program to print the sum of all of the nodes of this perfect binary tree. So if the tree is like below −So total sum is 30.If we see closer, we need to find the sum of all of the nodes. As the leaf nodes ...
Read More