C++ :: LinkedList Based Abstract Datatype For Pairs And Such
Feb 28, 2013
coming from Java, my experience with the Classes in C++ is quite limited.
Thats why I am having trouble converting the following (simple!) Java-Program.
Most examples with linked lists I found on the web describe how to implement the LinkedList class itself. But my problem is different: I want to use such a Class (I have a LinkedList class available on my system which is presumably OK).
Code: package main;
import java.util.ArrayList;
public class Main {
public static void main(String[] args) {
BoxList<String> sl = new BoxList<String>(
new ArrayList<ABox<String>>());
sl.getList().add(
new BoxPair2<String>(new BoxPair2<String>(
I have designed a class called matrixType that has some overloaded operators (+, -, *, and <<); the arithmetic operator functions of which are overloaded as member functions of the class. As an alert mechanism, I want a message displayed when two matrices of dissimilar sizes are added/subtracted OR when two incompatible matrices are being multiplied. Displaying this error message is not the problem. However, I want a scheme where on detecting two matrices’ incompatibility, the operator function returns the error message (a string datatype) instead of what would be an erroneous result (the expected matrixType object).
In other words, what I may be essentially asking is: Is it possible for a function, say,
I have a project to do in C and coming form Java I miss all the included features that are missing from C! I need to be able to store key value pairs in an quick and memory efficient manner. I've looked up using hash maps but I'm very new to C so don't really understand even the basic ones. I've looked at using a multi-dimensional array as I'm more comfortable with arrays but I'm unsure if that would count as a memory efficient and quick method?
But how would I do this using parallel_for_each (C++AMP) ? I need this for some algorithm that works with very long arrays and I think GPU would do this faster than CPU (even if I use all threads).
I am attempting to combine two vectors into a vector of pairs. I want to be able to alter the first and second of each pair and have those alterations reflected in the original vectors. I thought the following code might work but get compilation errors about a lack of viable overload for "=" for the line with the call to std::transform:
void f() { std::vector<int> a = {1,2,3,4,5}; std::vector<int> b = {6,7,8,9,0};
Alexandra has some distinct integer numbers a1,a2...an.
Count number of pairs (i,j) such that: 1≤ i ≤ n 1≤ j ≤ n ai < aj
Input
The first line of the input contains an integer T denoting the number of test cases. The description of T test cases follows. The first line of each test case contains a single integer n denoting the number of numbers Alexandra has. The second line contains n space-separated distinct integers a1, a2, ..., an denoting these numbers.
Output
For each test case, output a single line containing number of pairs for corresponding test case.
Constraints
1 ≤ T ≤ 4 1 ≤ n ≤ 100000 0 ≤ ai ≤ 109 All the ai are distinct
Example
2 2 2 1 3 3 1 2
Output: 1 3
Explanation
Case 1: Only one such pair: (2,1) Case 2: 3 possible pairs: (2,1), (2,3), (3,1)
as I understand the problem is just counting how many Ai's are 1 <= Ai <= N and then apply ((R*(R-1))/2), R is the count of valid Ai's
Problem is i dont know n so the solution must be recursive. The possible splits are 2^(n-1)-1. I am really stuck and most of the code is complete for cart and i really don't want to restrict it to binary values.
I have made a new data type which named LongDouble
it takes 16 byte to save the number the first bit for the sign the next 15 bit for the exponent the other 112 bit for the mantissa
I have to apply four operation on these numbers , but i have a problem in addition , when the sign for any of the numbers is negative ,how i can perform the operation , also if there is a Mantissa how i can also perform the operation?
if i try to save mantissa in a variable there would a loss of precision ... Here's my code
I just wanted to know a way to cut off any remaining zeroes from a double data type. I' trying to calculate cost and output it but it keeps adding a bunch of zeroes on the end. I know there must be a way to
I'm trying to write a simple program that finds the minimum difference between two pairs of integers in a list/array. Of no surprise, it not work the first time I ran it so naturally i chucked in a whole bunch of print statements to debug
I encountered a peculiar error that is really stumping me.
#include <iostream> using namespace std; int closest_pair(int arr[]) { int i=0; int j=0; int size=0; int min=0;
I'm printing the size of the array in main and inside the function...and inside the function its giving me a size = 2 which is incorrect though the size printed in main is correct (size = 20). I further narrowed down the discrepancy to this statement: sizeof(arr)
I have been writing a program to generate pairs of RSA keys using small prime numbers. I have been using mpz_invert() to get a value for d for the private key. On small prime numbers it calculates the correct value, but on larger primes it calculates incorrect values.
I'm assuming there must be an upper limit to the values the mpz_invert() function can handle? If so, what is this limit to avoid erroneous values?
How you would overload an operator for Common Data-types like "char" and "int".
I often use bool arrays to create a multilevel-trigger-systems, when iterating over multiple containers or waiting for two events to occur at the same time.
For example: I would define.. bool trigger[2] = {0, 0};
And when doing work via a loop, I use it like so: while(trigger[0] != 1 && trigger[1] != 1)
You can probably see where I'm going with this. I want to be able to use my bool array with the "!" operator.
So if "trigger == 0" (as a whole), it returns false.
How can I achieve this?
Can you create custom operators? Say if I wanted to create "or-gates" or "xor-gates" etc.
I am need to compare 2 items from 2 separate drop down lists. These values are of int type. Say for example 2 drop down lists showing years. Now i need to find out these 2 years selected is greater or nearer to the current year.
I tried converting the values i receive from the drop down lists to int variables. But i am getting error then. I gave it like below.
int tmp = Convert.ToInt32(ddl_1.SelectedItem.Text);
this gives an error like this - Input string was not in correct format.
I need to know how to put an item from a drop down list to a variable of int data type.
I have a class that is a template, I have to declare it in my main but i want the user to choose what type of data they will use in the class, I cant just declare myclass my, i have to use myclass<int> my, how can I change so user can select the proper datatype to use in the class.
I am writing a program that aims to be cross-platform, so it supports multiple low-level implementations for certain operations. My initial approach is to write an abstract class to use as an interface, and inherit from that when writing specific implementations.
However, I realized that the specific implementation that I will be using is known at compile-time, and I to not need any polymorphic behaviour. I realized that I could just write this:
Code: class Impl1 {}; #ifdef USING_IMPL1 typedef Impl1 Interf; #endif
Clients would then go on using the Interf type, regardless of the underlying implementation. The only drawback that I can see is that my Implementation classes are not forced to conform to an interface, but the compiler will tell me anyway if I try to use, in my client code, a method that is not defined.
I need to create a vector of pointers and hold the book objects in it. then i have a virtual function in my books which is a pure virtual in LibraryItems. When i try to add the books object in my code, i understand that since the scope runs out there is no object that is added. so when i run print it gives me an error.
#include<iostream> #include "books.h" #include "library.h" #include <vector> using namespace std;
int main(int argc, char * argv[]) { vector<LibraryItems* >libraryInfo;
I have this header file called Shape.h containing these function declarations. and a Shape.cpp which contains the body of the function. I am not showing it since it is not needed.
//This is from Shapes.h header file #ifndef SHAPES_H #define SHAPES_H #include <iostream>
[Code]....
I have this unfinished Main.cpp because the third line "JuanSanchez::Circle *pCar = new Circle; " is giving me a compiler error "error C2061: syntax error : identifier 'Circle' "
#include "Shapes.h" int main() { const int arrayIndex = 4; JuanSanchez::Shape *myShape[arrayIndex]; JuanSanchez::Circle *pCar = new Circle; }
class Element { public: .. virtual unsigned NumberOfNodes() = 0;
[Code] ....
Is it possible to implement this better? All the element stuff can be static, but this is not possible with the abstract class. I want to have Mesh independent of a specific element. With the code above, if I have multiple meshes I have one instance of an element, e.g., Triangle for each mesh. Although they are all exactly the same.
I am working on a project that requires me to create objects from a abstract class that has 2 child classes (that need to be derived). Any examples on how to do this? I looked online and the examples were pretty vague. the main error that I am getting is when I make a temp object with & in front of it (such as Employee &genericEmp) it throws a must be initialized error.
