What happens is, after having called the collisionDestroy-function and the program tries to execute the nest loop in the outer for-loop, it all crashes with the text "Expression: vector iterator not decrementable", which I understand is because the iterator will have already become useless. The question is: know this, how do I fix it? I can't seem to get a hang of it.
Here's the collisionDestroy-function (the collisionReaction does nothing but sets a few local variables):
void Enemy::collisionDestroy(std::vector<Sprite*>& sprites) {
for (std::vector<Sprite*>::iterator iter = sprites.begin(); iter != sprites.end(); iter++) {
Enemy* tmp = dynamic_cast<Enemy*>(*iter);
if (this == tmp && collisionType == 3 || collisionType == 1) {
sprites.erase(iter);
break;
}
}
}
I wrote this code, and everything was working well, but part of the assignment is that it must include nested loops. Once I added the nested while loop, which is basically an if statement, my life was ruined. I am trying to nest a loop in the code that will basically tell the compiler that if the value "loopVol" were to exceed the value of "final" after adding an increment, to run the program for the "final". How can I do that?
Example:
initial = 10 final = 123 increment = 10
as of now, the program would stop at 120, but I want to nest a loop that will tell the compiler to calculate at the final if this happens.
So I have a vector that I want to iterate through randomly, and by random I mean that each element is only accessed once but I don't want to shuffle the vector because the vector elements are large. So I want this functionality:
std::vector<SomeLargeObjectWithoutACopyConstructor> myvec; // ...fill myvec std::random_shuffle(myvec.begin(),myvec.end()); for (auto& value : myvec) { // do stuff }
Only I don't want to do this because the object type has no copy constructor and is large, so I don't want to shuffle the vector, just the iteration path. Is there a simple and efficient way of iterating randomly through a vector while ensuring that each object is only accessed once?
I need to iterate through a vector in a const function, and, as my function is called very often, to get more performances I need my iterator to be declared somewhere else than the function, so it doesn't have to get deleted and recreated over and over again. So here is my code:
The example enable a client to iterate the internal std::vector using being() and end().
Code: class foo { public: typedef std::vector<std::string>const_iterator iter; iter begin () const; iter end () const;
[Code] .....
In the future I see the need for this class to be able to control sequence (sorting) and also show a subset of the complete list based on a search parameter.
Using std::sort appear to solve the ability to sort the collection.
How can I return an iterator to the client which only iterates a sub-set of all items in the std::vector?
An example would be, I add this method to the class;
Code: void find(const std::string& st);
So if the client performs (below) only items in std::vector that contains the character "a" should be possible to iterate.
Code: foo f; f.search("a");
One option would be to operate with two collection inside the foo class. One more static containing all items and the other containing the sorted and filtered items. This would lead to some copying but should work. Far from perfect.
I'm having trouble getting my loop to work correctly. If I iterate the for loop once it works as expected and displays proper output. When I try to iterate two times or more the program gets stuck in an infinite loop.
I have a nested record structure in C++ that contains a FileHeader record, a RecordHeader record and a DataRecord record. The last item is an array of unknown size (at compile time). I have to open a file and read the array size and then create the array.
I have worked on this for some time and can't figure out how to make it work. I know the sample data I am using has 85 records. I insert 85 into the array size and it works fine. But how do I create a dynamic array or define a vector within a nested structure?
1. What is the best (easiest) method to accomplish this (array or vector)? 2. How would it be implemented/how do you add data to it?
PreviousLogRecord.FaultRecord.push_back(field1); // does not work PreviousLogRecord.FaultRecord[recordNumber].field1 = somedata; // works with 85 in array size. struct LogFileHeaderRecordType { QString field1; int field2;
Note: In this case, the values of x,y and z is integers from 0 to 3 inclusive.
For 3-dimensional space above, actually the code had run through 3 nested "for" loops.
Question: Above code works for 3-dimensional space. How to generalize the code, so that it works also for N-dimensional space, where N is an arbitrary integer?
I'm trying to output a pattern using loops. The pattern is a plus symbol made of 3 rows of 5 x's followed by 3 rows of 15 x's and finally 3 rows of 5 x's.
I can get the program to output all 9 rows with 5 x's but I don't know how to do the 3 rows of 15 in the middle. I have tried a while loop and also an if statement but nothing seems to work.
Basically after the 3rd run of the for loop, it encounters a contradiction. I want it to exit right there and then. Instead it continues to run the for loop. What can I do?
I'm writing a series of basic decipher programs and I have run into an issue where I get the correct answer when I start the loops at the iteration that contains the correct answer.
Code: // generate key "words" with length of 3 for (int x = 0; x < 26; x++){ for (int y = 0; y < 26; y++){ for (int z = 0; z < 26; z++){
[Code] ....
This is the essence of the loop, I've attached the program in its entirety if necessary. Basically what happens is if I start the loops at x = 17, y = 7, z = 12, then I get the correct decipher shifts but if I start at 0,0,0 whenever it gets to that iteration (12,000 ish) the shifts are off by 2 or 3. "koq" should translate to "the" but im getting "dcz". Is this a simple bug in the or is something moving to fast for something else to keep up?
And came across the following error during link stage: "/usr/include/c++/4.6/bits/stl_vector.h:1080:4: error: no matching function for call to ‘std::vector<cv::Point_<int> >::_M_fill_initialize(std::vector<cv::Point_<int> >::size_type, int&)’ "
I am attempting to read a file with 2 numbers in it. The first indicates the number of rows the second, the number of columns. So for a file (Data.txt) that contains the numbers 5 7, I want to display
and write that output to a file.I can display the correct number of rows and columns but I can't figure out how to display alternating rows of 0's and 1's.
#include <iostream> #include <fstream> using namespace std; int main() { ifstream inFile;//declare file
My program involves trajectory planning using cubic spline method for a robotic arm. In the process, I had to calculate joint angles for each point in the path. In the last few lines of the code I need to write the values for counter and theta1 into a text file which I called "Test.txt". I am doing this using a nested for loop(the counter runs until it reaches 19 and hence need 19 theta1 values corresponding to it). However, I can't get all the theta1 values transferred to the text file.The statement within my inner loop is wrong and don't know how to fix it.
We were discussing how to find average time complexity of different algorithms. Suppose I've a the following nested loop
for(int i=0;i<n;i++) { min = i;
[Code].....
Now the outer loop will iterate N times. the inner loop will always iterate 3 times no matter what the value of N is. so the worst case time complexity should be O(n^2) but what about the average case and the best case? I mean in terms of searching we can figure out and distinguish between the worst,best and average as it depends upon the number of comparisons. But here how can the average and best case be different then the worst case.
I'm trying to use a priority queue sorting in reverse order to take a vector or 2d array. The problem is that I want to sort by the vector/array cell value but keep the reference to the vector/array index of the value. I don't know quite howto keep them both related so when I pop. I can find the corresponding cell.
I am trying to make an add-on to IE. This add-on doesn't have any tool bar or any UI.
I am just taking the details of currently loaded HTML page. Basically it is for manipulating one dialog box. I want to get access to the DOM COM interfaces of the dialog box.
Since it doesn't have any button I didn't impliment IOleCommandTarget. I implemented only IObjectWithSIte.
My RGS file contain following in addition to my COM related entries
HKLM { NoRemove SOFTWARE { NoRemove Microsoft {
[Code]...
But I couldn't see my add-on working or even not loading to IE.
