This is simple recursive solution of Fibonacci number:
Code:
int fibo(int n)
{
if(n<=1)
return 1;
else
return fibo(n-1)+fibo(n-2);
}
Now the recursion will generate a large recursion tree, like if n=5, 5 will call (5-1), (5-2) or 4,3 . What I want to know is, will fibo(n-1) will be called 1st go all the way to the base case 1, then do the summation or fibo(n-2) will be called right after fibo(n-1) ?
i want to write an array sorting program that works with recursive function.but i can not do it.
my algorithm
Recursive
find the min value
find the min value and save it
find the min value and save it and remove it from loop
put the rest in loop again
find the min value again
..
...
i didnt write the function because i dont know how will it work
Code:
#include<stdio.h>
#include<stdlib.h>
#define s 5
void main() {
int a[s]={25,3,2,4,1},c[s]; // c[s] for new sorting
int i,ek,j; //ek = min
[Code]....
I have a multi-thred piece of code that should be fast. As I have to update a Database from time to time, I wonder if I do it in a prpoer manner with calls like this:
Task.Factory.StartNew(()=>update_execution_to_db(exec));
Those are my sporadic updates, my ongoing update have a queue and a dispatcher thread reading from the Q, I just don't want to use this overhead for the sporadic updates.
Code:
class A {
virtual method1() { };
};
class B : public A {
method1() { }
}
Code:
A* a = new A();
a->method1(); // call B's method1?
Is it possible to call B's method1 in this case?
Let's start with something from the c++ reference:
... delete[] is an operator with a very specific behavior: An expression with the delete[] operator, first calls the appropriate destructors for each element in the array (if these are of a class type) ...
I was wondering if I can tell delete[] to not call destructors, for example if I already know that the delete[] statement should be delete without []. That would be very useful for memory management/memory leak detection.
I'd like to know what happens if I use multiple calls to malloc() on one pointer (without free) in a single function. Here is the example:
void *data_thread(void *sockfd_ptr) {
int sockfd = *(int *) sockfd_ptr;
const int BUFSIZE = 5;
char recvmessage[BUFSIZE];
char *headerstr = NULL;
char *newheaderstr = NULL;
[code]....
what happens with newheaderstr every time malloc() is called. There isn't a realloc() or anything. I didn't think it looked right to keep using malloc() like that.
The below code is taken from open source filezilla project
(FileZilla_3.7.3_srcfilezilla-3.7.3srcinterfacebookmarks_dialog.cpp)
Code:
#include <filezilla.h>
#include "bookmarks_dialog.h"
#include "sitemanager.h"
#include "ipcmutex.h"
#include "themeprovider.h"
#include "xmlfunctions.h"
BEGIN_EVENT_TABLE(CNewBookmarkDialog, wxDialogEx)
EVT_BUTTON(XRCID("wxID_OK"), CNewBookmarkDialog::OnOK)
EVT_BUTTON(XRCID("ID_BROWSE"), CNewBookmarkDialog::OnBrowse)
END_EVENT_TABLE()
I'm unable to understand what are these lines after the #include. They don't end in semicolons. Looks very much like function calls.
Are BEGIN_EVENT_TABLE, EVT_BUTTON and END_EVENT_TABLE function calls? Function calls should end with semicolons right?
I created a server application but i need to know how to delete my calls to new
Code:
CBaseServer::CBaseServer() {
}
CBaseServer::~CBaseServer() {
}
void CBaseServer::Start() {
struct sockaddr_in ain;
[Code] .....
Also when I call this..
Code:
new CThreadManager();
It gives me this warning...
warning C4345: behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized
I have several functions doing similar things, inside their implementations, the parameters are the same, but they call different methods.
I want to create one function to make the structure easier, and reduce the duplication. I heard template might be one solution. But I am not sure how to use it in this case.
void GetA(...XXX) {
for()
{
[Code].....
My function "MatrixMul" returns an int array with multiple values Let's say, res[0] and res[1]
When I'm calling the array in a for loop for multiple times, and when I'm storing the results in another array, in each iteration the results are over-written with the new results.
If the first call returns [0,1] the array will store [0,1] at index [0] and [1], which is fine, but when I'm calling the function again, the new results are stored at the same indexes [0] and [1] How can I avoid that?
The code is:
class Hill_Cipher
{
string AtoZ="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
public string Hill_Cipher_Enc(string input, int[,] key)
[Code].....
For example, my outPut contains the following: "TH","IS","AT" when I'm calling the function with the first element of array "TH", it converts "T" to its equivalent number and apply some calculations and same with "H". Let's say the final answer is 20 for "T" and 30 for "H". The problem is that every time, encChars will store the values at index 0 and 1: encChars[0]=20 encChars[1]=30 When I call the function again it will store the new values at 0 and 1.... That's because I'm not changing the index value for encChars on each call, so how do I do that?
Code:
scanf("%d", &a);
printf("A");
scanf("%d", &b);
prints "A" after calling scanf two times instead of between the calls (first scan, then print, then scan). I'm using GCC v4.6
I'm trying to implement a code that recursively calls itself and prints the given digits in ascending order, i.e. if the number is 5, then the function will print 1 2 3 4 5. I cannot use loops in any way!
The problem I have is with keeping my variable i at a set value each time the function calls itself.
void print_ascending(int n){
int i = 1;
if(i < n) {
printf("%d", i);
i++;
print_ascending(n);
}
}
Of course, the problem with this code is it will re-initialize the variable i to 1 every single time and infinitely loop to print 1.
I need to be able to disable the items on a CCheckListBox but I can't change the code that calls AddString. I know I can use the CCheckListBox::Enable function to disable an item if I have an index but I don't have the index which would be provided by AddString.
I've tried intercepting the LB_ADDSTRING message and then looping through the items in the control but the string has not been added at this point so the last item in the list is never disabled.
I used Spy++ to see what messages were being sent and I noticed that LB_GETTEXT was sent so I tried intercepting this message (ugly hack) but this caused my app to hang - I assume because of the number of times the message is sent. Is there a way to disable the items?
I'm having a really dumb moment and I cant seem to remember how an if statement works, with only the variable name as the condition..
Code:
if(var){
//then do something
}
My code has been acting odd. I made a function that layers my art resources but only the last tile of my art resource acts the way it should. My character goes behind and in front of the last tile and gets printed correctly. Strangely its really exclusive to the last tiles I print. What I need is to figure out in step by step order what going on with my code sample below and be able to layer the resources.
Here is a small sample of my main function. This is how I do my rendering.
Code:
Int main (int arc, char* args[]) {
//Move class
Move character;
//Class Tile & Side Tile
Tile *tiles [TOTAL_TILES];
[Code] ......
How the getline function works.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main() {
[Code] ......
getline(&inputstr, 128, NULL); getline gets a line in a data file.
I assume that inputstr[128] is the name of the file? why is the number of the array in the getline function....
i want to ask how does malloc works on an array for instance can i dao this
Code: p=100;
int array[10];
array = malloc(p * sizeof(int));
then will the size of int be 100 so will i be able to do like
Code:
array[11] = 12 ; ???
also if i have a 2d array how can i use malloc on it and how does this works with pointers????
I know how exception handling works, but how should I actually use it in action? Let's say I have something like this:
Class X
{
public:
X();
//Pre-condition: example can't be 3.
void number(int example);
[code]......
If I know that the exception can only happen at the beginning of the function, is it okay to catch it right away?
I have this following piece of code:
int id = 5;
const char *ptrId;
ptrId = ( int_to_str(id) ).getPtr(); // Works in Solaris well
But the above code prints some junk values when I run the same on Linux machine. But the following works well on Linux:
String temp = int_to_str(id);
ptrId = temp.getPtr();
The prototype of getPtr() is:
const char* String::getPtr() const
Okay so I am programming an 8051 variant to interact with an SD card. In a separate initialization routine in SD_CARD.c I pull out the vital information of the card into global variables. I then call Menu() which is in another source file but includes a header file with all of the variables declared as extern. Now here is the weird, part this is from my Menu.c
printf("%u" , VOLUME_1_SECTOR);
if(VOLUME_1_SECTOR==16384)
printf("Correct");
else
printf("Incorrect");
Now the output of the first printf is 16384 but the conditional evaluates to false. If I put this code in SD_CARD.c (Where VOLUME_1_SECTOR is defined) the conditional evaluates to true. I am confused why the printf works correctly in Menu.c but not the conditional.
when i was finding a way to concatenate three integers in C, I came across a snippet like this
Code:
#include<stdio.h>
#define cat(a,b,c) a##b##c
int main()
{
int d;
d=cat(1,2,3);
return 0;
}
How the macro works here? I am unable to understand the function '#' plays in the macro.
I tried writing a program for finding the area of a circle, and I'm wondering why it only works when i define it as 'float', but not as a double?
Code:
#include <stdio.h>
#define pi 3.14159
double
main(void)
[Code] .....
Assignment: Take an integer keyed in from the terminal and extract and display each digit of the integer in English. Ex. 932 --> nine three two
Code:
/*This program takes an integer keyed in from the terminal and extracts and displays each digit of the integer in English.*/
#include<stdio.h>
int main(void)
{
//DECLARE VARIABLES
int num;
}
[code]....
I don't know how the program works if the integer is more than one digit.
I have a question about a dynamically loaded library I am using. I have called it SqlWrite, it is for connecting and writing to a Microsoft SQL server DB. I have a function in it that is defined as:
extern "C" {
__declspec(dllexport) RETCODE __cdecl SqlExecS(SQLHANDLESTR* h, LPCSTR Statement) {
RETCODE RetCode;
std::string input = Statement;
std::wostringstream conv;
conv << input.c_str();
std::wstring wCmd(conv.str());
[Code] ....
I then load it in another MSVC project as:
#ifdef WIN32//C:UsersaDocumentsVisual Studio 2012ProjectsGetPageSourceDebugGetPageSource.dll
#pragma message("WIN32 is defined")
#ifdef _DEBUG
SetErrorMode(0);
[Code] ....
As you can see, inside the prototyped function "SqlExecSP", I cout (or, rather, wcout for wide characters) the sql statement i am running, and the return code of the sql statement. a sql return code of "0" is equivalent to "SQL_SUCCESS". Then, I cout " got player again " after executon of SqlExecSP alias SqlExecS.
This usually works, and gives me following sample output:
exec SELECT [PlayerID], [FirstName], [LastName], [TeamID] FROM [soccer].[dbo].[Players] WHERE LastName = 'Abdellaoue' AND FirstName = 'Mohammed' retcode 0
RETURNING FROM EXECSP NOW!!!
got player again
However, sometimes, the program crashes somewhere between outputting "RETURNING FROM EXECSP NOW!!!" and outputting " got player again ", i.e. the output is then:
exec SELECT [PlayerID], [FirstName], [LastName], [TeamID] FROM [soccer].[dbo].[Players] WHERE LastName = 'Abdellaoue' AND FirstName = 'Mohammed' retcode 0
RETURNING FROM EXECSP NOW!!!
As you can see, it doesn't output the next line " got player again ", because it somehow crashes in between.
However,t he only line that should be executed between this, as far as I can understand, is the actual return of the DLL function SqlExecS, prototyped as SqlExecSP in my calling code, i.e. the only line that should be executed in between is:
return RetCode;
However, somehow, this fails, even though RetCode is "0", as I can see at the end of the output
exec SELECT [PlayerID], [FirstName], [LastName], [TeamID] FROM [soccer].[dbo].[Players] WHERE LastName = 'Abdellaoue' AND FirstName = 'Mohammed' retcode 0
Now, why sometimes this crashes, and sometimes this works. I.e, I can sometimes call this function x times, and it doesnt fail, outputting " got player again " right after the calls, and sometimes, it fails somewhere in between, at call x, y, or z, i.e. sometimes i can execute it ten times successfully and sometimes i can't, even though the return code is still 0, and it just fails somewhere in between. I am not sure if it has to do with the call being a call to a dynamically loaded DLL function, but I can't see where else the error is.
Why this can be failing, and at different, seemingly random times?
i've got an assigment that requires me to overload some operators and add some objects together.
I will show the code and explain as good as I can.
void SArray::operator+= (const SArray &obj)
{
Sphere * tmp_arr;
tmp_arr = new Sphere[obj.antalobjekt+this->antalobjekt]; //antalobjekt = //Gets amount of elements in the arrays.
[Code]......
m_arr is the inner array for storing elements, do ask if something is not clear enough. The copy constructor works, so i have not included it.
My program works primarily by receiving user input however; using 'char' and 'fgets' i have to stipulate how many characters i want assigned, and this isn't practical for what I am after. Example below.
Code:
char example[50];
printf("What colour is the sky?
");
fgets(example, 50, stdin); Is it possible that the assigned number (in this case '50') is determined strictly by the user input?
for example, user input is Blue then 50 is then 5?