C++ :: What Is The Reason Of Trashing A Container Variable
Mar 9, 2012Sometimes a variable or a map would get trashed after it has been found valid somewhere else.
What is the probable cause of this kind of error?
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C :: Program Exits For No Reason?
Apr 29, 2014Code:
#include <stdio.h>
#include <stdlib.h>
void f(char letter,char *str) {
int i=0;
char CAPletter = 'A' + letter - 'a';
[Code] .....
OUTPUT:
//substrings starting with 'letter'
name
niros
NIce
Everything works but program quits and don't stay in console.
C# :: Code Was Skipped While Debugging For No Reason
Oct 6, 2014I have something like this
string rid = row.Cells[0].Value.ToString();
string identification = row.Cells[9].Value.ToString();
IDLabel.Text = "ID: " + rid + " <Identification: " + identification + ">";
I checked that while identification has a value, the IDLabel.Text was run just fine, but if identification has null value, IDLabel.Text was skipped totally...
C++ :: Tile Map (unknown Reason For Unresolved External Symbols)
Nov 7, 2013So I tried to make a tile map function to display my map as tiles. I keep getting unresolved external symbol errors, I've included the header file, and used every declaration in it, but to be completely honest this is mostly just a try to see if I could do it, and so far I'm failing. So if you can see why I'm getting the error.
header tileMap.h:
#include<SFML/Graphics.hpp>
#include<iostream>
#include<fstream>
#include<string>
#include<cctype>
#include<vector>
class tileMap{
[Code] .....
output message:
1234567891011121314
1
1> main.cpp
1>c:users wiggystardustdocumentsvisual studio 2010projects ilemapenginemain.cpp(21): warning C4018: '<' : signed/unsigned mismatch
[Code] ....
C++ :: Text To ASCII - String Loses Its Value For No Reason Apparently
Mar 26, 2014I need to make program which converts text (letters and digits only) into 7-digit ascii code. The start and end code is "1100011", so it must not appear inside the output code, thus a zero should be added in it (11000011).
Not that it matters much what my task is - I have a problem. Here's the code:
Code:
#include <iostream>
#include <stdlib.h>
using namespace std;
int main() {
string in,out="",pk="1100011";
getline(cin,in);
[Code] ....
The 'pk' string loses its value here when I enter a character in the input and I cant figure out why... I got that the problem is somewhere in the first if loop, since the code prints pk nicely when cout is before the loop (comment 1)..however, after the loop (comment 2) it prints nothing..... When compiled, it works nice when I input numbers, but 1 character - and 'pk' disappears...
C++ :: What STL Container Should Be Used For Inventory
Mar 27, 2014So I'm writing an RPG and I'm in need of an inventory system. Of course as an relatively old member of the forum I know best than just come here and ask so I've already researched quite a bit and I've formulated this idea.
I've kind of conceptualized it like so: I'll have some sort of STL container of a unique_ptr of my base item class. There will be derived item classes. Taking advantage of polymorphism I can then call the new Derivedclass when inserting it in the STL container.
My questions are: What STL container should be used for the inventory(fixed sized)?
C++ :: What Is Container Class
Sep 22, 2013What is container class? what its advantage ?
View 2 Replies View RelatedC++ :: Which Std Container To Choose
Sep 16, 2012I have a pile of data, which i need to access frequently and fast. One entry consists of two unsigned ints, let`s call them source and destination.
One source can have several destinations, but this rarely ever happens. Several sources can have the same destination - this happens more frequently, but still scarcely.
Once the data is set up, it rarely ever changes - yet it should be possible to add or remove entries.
I now need to find all sources for a given destination, or all destinations for a given source.
The question: which stl container to choose?
I have tried a multimap, using the source as key. This works good for finding all d for a given s, but is inefficient in the other direction.
Do you think it would be more efficient to have two multimaps, sorted respectively by source and destination?
C++ :: Multilevel Dynamic Container
Mar 6, 2013I am trying to come up with a way to make use of a "multilevel dynamic" container. I am parsing a file to grab some pieces of data. Lets say the first field of data I find I push into an array. At the same time lets I wish to create 2 cascaded sublevels. So an element in Modules is a pointer to the Types vector associated with that module and each element in Types is a pointer to a vector of Data. This concept should be similar to memory paging.
/*
Modules Types Data
____ _____ ______
|____|------> |_____| ---------->|______|
|____| |_____| |______|
|____| |_____| |______|
|____|
|____|
|____| _____ ______
|____|------> |_____|----------->|______|
|____| |_____| |______|
*/
Obviously this becomes very hair quickly so it is obvious that I need to dynamically create and destroy vectors (if I do it this way). Should I just create pointers using the new operator?
Here is some of my code if it is even worthwhile to read:
class Parser {
//storage arrays
vector <string> modules;
vector <string> terminal_type;
vector <string> tag_type;
vector <string> data;
[Code] ....
parse this stuff and nicely organize it.
If you take the first one, "max_logvar" is a module so everything between < and > is associated with that module.
symb is unimportant for now.
then "proterm" is a "module type" so then module now needs a module type container but I may have more than one of those.
so then I break it down by "Input" and "Output" where each of those can have the integer values (just in an array where each position will be set) that are in the fields to the right.
C++ :: Deleting Object From A Container?
Nov 21, 2013I have a container in c++11 and i must delete first object and i don't know how...
for (const prob& p : *static_cast<vector<prob>*>(list.listData)){
// i must delete the first object
}
C++ :: Container Of Hierarchy Of Objects
Apr 25, 2014How do we design a container of objects all of which belong to some subclass which directly/indirectly inherits from a given parent class? Moreover, I would like to have functions that enable me to pick only objects of a certain class type from the container.
For example if the parent class is A and I have a hierarchy of classes that derive from it, we must have a container that can contain any class that exists in this hierarchy. Also, get_B() must be able to let me examine only those objects in this container that inherit (directly/indirectly) from class B (class B exists in the hierarchy rooted at A).
Preferably, we would like to avoid downcasting. Or even explicit typechecking of any sort.
C++ :: Relation Between A Container And Allocator
Mar 30, 2014To my understanding, a Container should have an Allocator member data, which is used internally.
Question: what happens, for example, when we swap() two containers that use different allocators?
Must the allocators be swapped as well?
Must all elements of the container be reallocated when the allocator is changed?
C++ :: Bidimensional Array Container
Jun 24, 2013I need to create an array container with the same structure as double myA [100][100];. But I cannot declare it as array<double, 100, 100> myA; however I do need this container for its format. How can I make it work.
View 6 Replies View RelatedC++ :: How To Create A Container Class
Feb 9, 2013I know that it's a class that contains data from another class I just do not know how to make them both work together.
View 1 Replies View RelatedC++ :: Building A Typeless Container?
Jun 14, 2013i built a programming language called jade that right now can only print. i want to add variables to it however. I am going to use a modified bajarne stroustrop calculator to handle expressions (ie will now include string manipulations and such), but I want to build a var class into the program to make it easier for the program. i want variables to act like python variabes, and arrays to act like python associative arrays. Ive scoured different containers, but they only work if the variable isnt an array in my language, because it will only have one type. the only thing i can come up with is a union and 4 overloaded = operators (for bool, int, double, and string) is there a better way to do this?
View 2 Replies View RelatedC++ :: How To Properly Iterate Over A Container
Oct 31, 2013so i have a container called Source that is of type std::map<std::string, std::vector<std::string>> but when I try to print it with this function:
void Lexer::PrintSource()
{
for(auto Iterator = this->Source.begin(); Iterator != this->Source.end(); Iterator++)
for(auto SubIterator = Iterator->begin(); SubIterator != Iterator->end(); SubIterator++)
cout<< *SubIterator << endl;
}
i get these errors:
Lexer.cpp: In member function 'void Lexer::PrintSource()':
Lexer.cpp:29:42: error: 'struct std::pair<const std::basic_string<char>, std::vector<std::basic_string<char> > >' has no member named 'begin'
for(auto SubIterator = Iterator->begin(); SubIterator != Iterator->end(); SubIterator++)
^
Lexer.cpp:29:76: error: 'struct std::pair<const std::basic_string<char>, std::vector<std::basic_string<char> > >' has no member named 'end'
for(auto SubIterator = Iterator->begin(); SubIterator != Iterator->end(); SubIterator++)
^
C++ :: How To Delete A Container From A Deposit
Nov 23, 2013I have a deposit of containers and i must delete the cats container. How i can do that?
#include <iostream>
#include <string>
#include <vector>
using namespace std;
struct Cat {
string name;
int age;
[Code] .....
C++ :: Array Container For Loop?
May 13, 2014I want to find all instances of a substring mysub in array container myarr and replace each occurrence of mysub with empty string " ". To do that, I'd like to use for loop with search algorithm.
Code below:
p=array iterator
for ( p=search(myarr.cbegin(),myarr.end(), mysub.begin(),mysub.end();
p!=myarr.end();
p=search(p,myarr.end(),mysub.begin(),mysub.end() ); {
[Code] ......
C++ :: Accessing A Table By Container
Jun 30, 2014I need a "meaningful" way of accessing a table, the column is representing Err magnitude, and the row is representing Rate magnitude. For each error magnitude and rate magnitude, i define an action magnitude, which is the contains of the table. For example,
Code:
int matrix[10][10];
int Action1 = matrix[0][0];
int Action2 = matrix[0][1];
However, i need a better way of getting matrix[0][0], row and col itself is meaningless. I want to access the table like
"Action magnitude" = matrix["Rate magnitude 1"]["Err magnitude 2"]; using a string instead of int id.
How to easily do this in c++ container?
C++ :: Best Std Container Class For Application?
Jan 16, 2012I have a class called CTestObject and it has one variable int id. I want to add instances of this to an std container and be able to:
1. quickly determine if the value of "int id" exists in the container and update the object
or
2. add a new object to the container
Which std container is the best for this application? What method should I use to search the container for the object id?
C++ :: STL Container And Algorithm Requirements
Feb 21, 2012How do you find, when you first introduced with say some of the STL container, function or algorithms, what are its requirements? I mean,
1. what operators object should have for specific container?
2. what function args and type it should return for a algo?
3. when extending some container like with custom allocator, char_traits...and what not, what methods should be overridden? What work should they do?
C++ :: Std Container Iterators - Category?
Jun 15, 2014When using an iterator with a std container (list / vector etc) sometimes it's possible to modify the container (e.g. delete an item) yet still carry on using the iterator - whereas in other cases, modifying the container immediately invalidates any open iterators on it. Is there an easy way to know which containers fall into which category? (or does it vary from one compiler to another?)
View 2 Replies View RelatedC++ :: Writing A Program Without Using Any Type Of Container
Jan 19, 2014How to write a program without using any type of container .
View 4 Replies View RelatedC++ :: How To Store Data From A Class Into A Container
Feb 10, 2013I'm having trouble understanding on how to actually store into a container from another class. Any simple example.
View 9 Replies View RelatedC++ :: Vector Like Container Which Can Reuse Space?
Dec 24, 2014Unoptimized problem: I work on a table (vector of vectors). vector< vector<double> >
Optimization: If the current set of vectors is v1...vn (so each vk is a vector of double), my problem is such that I will only work on the last M of the vectors, the earlier vectors are irrelevant. I would like to reuse space to make the algorithm scalable, so I want to delete the vectors that can be forgotten. I read in a new vector, I delete the oldest vector.
C++ :: Inheritance Info Lost In Container?
Sep 16, 2013Code mostly speaks for itself:
#include <list>
#include <iostream>
using namespace std;
[Code]....
I added an object of class myderiv to the container, but when I retrieve it back and try to manipulate it, it's actually of class mybase. Is there any way to keep the inheritance information in the container?