How to output vector contents using the push_back function. My program reads in values just fine, but it does not output anything and I've been stuck on why.
here is my code:
#include <iostream> #include <array> #include <vector> using namespace std; int duplicate( vector < int > &vector1, const int value, const int counter)
Code: class moClassValueContainer { public: moClassValueContainer(); moClassValueContainer(string,int); [Code] ....
In my main.cpp, I have blow loop
Code: for (xml_node tnode = it->first_child(); tnode ; tnode = tnode.next_sibling()) { Container tmpContainer(tnode); if (tmpContainer.getType() == SINGLE) { string t = tmpContainer.getName();
[Code] ....
I cannot push_back(t). I examined the code with debugger, t has correct string value assigned, but even after 20-30 iterations, there is no element for headerFields vector.
#include <string> #include <vector> using namespace std; class Question { string title; vector<Thing*> posAns; vector<Thing*> negAns;
[Code] ....
error: no instance of overloaded function 'std::vector::push_back()' matches the arguments list argument types are (const Thing *) object type is: std:: vector<Thing *, std::allocator<Thing *>>
So it cannot be constant, what if I just leave it non-constant? Will it be safe?
I was wondering if it's possible to push a button on a website programatically. Unfortunately the button link is invisible, otherwise I could simply use the URL it links to. So is there a way to do it in c++ and if so, how?
I am trying to use push back in a 2D vector but I don't know how to. This is what I have:
vector <vector <BigInt> > matr;
for (BigInt i=0;i<rij;i++) { for (BigInt j=0;j<kolom-1;j++) { matr.push_back().push_back((i+1)^(pow-j)); } }
I quickly invented something but that doesn't work obviously. it should be equivalent to this: (the only problem in the code below is that those indexes don't exist yet that's why I need push_back())
for (BigInt i=0;i<rij;i++) { for (BigInt j=0;j<kolom-1;j++) { matr[int(i)][int(j)]=(i+1)^(pow-j); } }
However, when I print out the values stored by the pointer vector, the first 2 values are not the same as what the input was. I have tried it with 4 - 10 values and always, the first 2 are not the same as the input but the rest are. I tried printing out the values as they are stored in the vector in the first for-loop and it seems to contain them all, but after that first for-loop, when I try to print *station.front(), it is now changed to something else.
I want to know this because if I happen to want to use a lot of insertions and deletions then it is more efficient to make use of Linked List instead of Dynamic Array.
While, if I happen to want to just access random parts of the Array, then Dynamic would be more efficient.
I want to make a 2D game using SDL engine and I need to check whether or not an object is colliding with a list of other objects. (because there would be more then one objects on the map.)
Since I would simply be accessing each object sequentially to check whether or not the object is colliding with another the object in question, and since any of those objects could "die" and be deleted at any time, it makes more sense to use Linked List then a Dynamic Array.
I've been playing around with making a linked list in C and am having trouble adding to the beginning of the list. For the add_beg() function: the statement "head = newNode" only works locally. This leads me to believe this is a pointer problem. However, the add_end() function works correctly. Ideally, I would like to print "0 1 2 3 4" after using the add_end(root, 0). Currently, print only gives me "1 2 3 4".
#include <stdio.h> #include <stdlib.h> //Create a node struct typedef struct node { //data int val;
Here are the segments of me trying to push the packets onto a vector:
[code] std::vector<size_t> processing_queue; //HERE IS WHERE I'M TRYING TO PUSH THE PACKETS ONTO A VECTOR processing_queue.push_back(num_rx_samps); [code]
I previously had my program saving to a .dat file (the commented out lines), but I need to change it to pushing values onto a vector so I can stream the data packets from the ethernet cable to be processed. However, the packets aren't being pushed onto the stack as I suspected. What do I need to change to push the data packets onto a vector? The following is the code:
How to avoid using Backspace character with push_back? I'm making a software as an ATM, so when the user try to enter the password the user only sees *******, but when trying to delete it doesn't delete a character. It just adds a new one. Here's my code:
std::vector<size_t> processing_queue; //HERE IS WHERE I'M TRYING TO PUSH THE PACKETS ONTO A VECTOR processing_queue.push_back(num_rx_samps);
I previously had my program saving to a .dat file (the commented out lines), but I'm trying to change it to pushing values onto a vector so I can stream the data packets from the ethernet cable to be processed. However, I'm having issues with pushing the data packets onto the vector?
I am having trouble putting data from a txt file onto a vector of a class. For instance.
class employee{ setname(string) { some code } getname () { some code } setid(int)
[Code] ....
How would use my setname function in my class using my vector? I tried doing vec[num].setname(tempname) but it doesn't work. I know it does not work because I have to use .push back for a vector but I don't know exactly how to pushback using the set name function call.
I am trying to write a method (copyStack())that copies the elements of one stack to another. So I am using a Type variable and a while loop, assigning the top of the first stack to the variable, and then using the push method to push the Type variable into my second stack (then poping the first stack). However, whenever it comes time to print the second stack (the one I am trying to copy into), nothing shows up. I know that the program is reaching the copyStack function, and I know that when I put a regular string in for the Type variable, it passes that string along. But for some reason, when I use the variable, nothing happens! Here's what I've got...
Overview of problem : I am using std::vector to hold objects of Subject. Now this vector contains lots of objects( with lots I mean 10-20 objects at max) . These objects have string member values like category and sub_category. Both category and sub_category can have string which can be same of other objects's sub_category & category.
Issue: Now I want my std::vector to have only those objects whose's sub_category are unique. If category is not unique that's not a problem .
Secondly if we found 2 objects having same sub_category then we have to delete one of them from the vector. we will delete it based on some rules example
Rules for deleting are if
i) instance of Subject ->category = " Land " OR if category = "Jungle" then delete other duplicate object , ii) if above condition doesn't match then delete either of them.
I am wondering , how would I compare the sub-items from the vector . For example. I have class say Subject
class Subject { public : // some constructors, // functions to get ., set category and sub category std::String get_sub_category() std::string get_category(); private: std::string category; std::string sub_category; }
I have vector which stores object of Subjects. Example : vector<Subject> copy_vector;
Now what I want is to delete the object from vector that has same sub_category I am not looking for source code buT i need a starting point,? Example:
copy_vector[0] = Animal object that has sub_category Tiger copy_vector [1] = Animal object with Lion as sub category copy_vector[2] = Forest object with sub_category Tiger
What I want is to based on some conditions(which I can do ) remove either Forest or Animal object containing Tiger. But for that how would I do comparison? I have written the function and have checked it.
std::vector< Subject >copy_vector; // copy_vector contains all the objects of Subject with redundant sub_category for( std::vector< Subject >::iterator ii = copy_vector.begin() ; ii != copy_vector.end() ; ++ii ) { sub_category = ii->get_sub_category();
1. I have some vector<unsigned char> containing binary data. I would like to combine them into one std::string. How is the correct way to accomplish this?
This is my best guess for sample code:
Code: vector<unsigned char> data; //conatins some data vector<unsigned char> data2; //contains more data string temp(data.begin(), data.end()); temp.append(data2.begin(), data2.end());
Will this code work with binary data, or will it null terminate?
2. A similar problem.. I have some unsigned char* variables, and I want to combine them into one std::string. How can I accomplish this? will the member append() work here? or will it null terminate? Something like:
Code: unsigned char* data; //conatins some data unsigned char* data2; //contains more data string temp(reinterpret_cast<const char*>(data)); temp.append(string(reinterpret_cast<const char*>(data2)));
Will the above sample code work without null termination?
I have a thread with a while(1) loop in it. When the user push the stop button I would like that thread to end.
I thought about creating a bool and checking its value periodically in the thread and when I push the stop button I change the value of the bool for that the thread breaks out of the loop and finishes.
I am working on my second c++ project that is a statistical analysis of a vector data set of integers. I created a struct called range with a maximum value, minimum value and count for occurrence. The frequencies are stored in a vector<range>.
I have tried messing around with the increment to get the high range test above the maximum element, though my ranges cumulatively increase by 9.9. I'm not sure how the professor's program has the distance between high and low ranges as 10 instead of 9.9, which is the increment. I'm also unsure why half way through his buckets, the ranges appear as 9.99 briefly and then return to 10 after (40.00 - 49.99 then 49.99 - 59.99). I feel like I am missing something very obvious on line 04 or 10 in my code.
Here is the code for the frequency that accepts a vector reference for my data set of integers.