I'm confused with this last [for] loop; How is ptr++ applied for non-integer value? Ptr is clearly a char, it comes from str, which reads string line from file.
I come from C# background, I have never met for...loop which irritates by using [somechar]++, not [someinteger]++;
What is actually going on there?
Some other similar example might be:
Code:
(iColor+(_parts[j]%length)*3),
where iColor is static unsigned char iColor[] array;
I would expect to see iColor[somevalue] + (_parts[j]%length)*3), but here in C++ I sometimes see that integer is being added directly to the array. What does it mean, what happens?
Alright, so I have a code that's not giving me errors, but it doesn't seem to retain what I put into an array. Not sure If I'm missing something...
Code: #include <stdio.h> int main (void) { const char *pointer; const char alphabet[] = "ABCDEFG";
pointer = &alphabet[5]; printf("pointing to %c of the alphabet ", pointer); return 0; }
Trying to get my pointer to return the letter in the [5] spot or "F". Not receiving any errors when compiling, but I seem to get different answers every time I run it.
I'm trying to create a simple calc program that does all the elementary calculations. How to get it to add and multiply continuously without crashing. but now i need to figure out how to ask the user if they want to continue or not. I'm having trouble here because in the while statement i have a scanf which asks for the operator symbol. and then asks for number in the second scanf..
So basically a user would have to enter 'R' twice for the message to pop up! Also i'm not sure how i would quite the program if they put in a 'N' for no. would return 0; work? What if they press 'Y' for yes, what would the return have to be then?
Here's a snippet of the code int main () { double result; double new_number; char symbol; result = 0; while(1==scanf(" %c", &symbol) && symbol == 'R' && symbol =='r')
I have two files like original.txt and replace.txt which has equal nbr of lines in both of them.
I need to loop through these two files line by line and replace the line in original.txt to the line in replace.txt
eg :
output.txt :
1|raj|65.4|Y| 1|ramesh|65.4|Y|
replace.txt :
1|raj|65.4|Y| Cannot be processed|1|ramesh|65.4|Y|
What I need here is when reading of output.txt reaches second line of file "1|ramesh|65.4|Y|", it has to be replaced with the second line in replace.txt "Cannot be processed|1|ramesh|65.4|Y|".
1|ramesh|65.4|Y| --> Cannot be processed|1|ramesh|65.4|Y|
After the end of loop the contents of two files should be like :
original.txt :
1|raj|65.4|Y| Cannot be processed|1|ramesh|65.4|Y|
replace.txt :
1|raj|65.4|Y| Cannot be processed|1|ramesh|65.4|Y|
The files can have variable number of lines but both will have same number of lines each.
I need to do make a loop inside a condition. Can it be done? I don't want to call another function to do it. Any way at all without calling separate function inside the if? I just want to do:
if ( for (int i = 0; i<=10; i++) { //stuff related to the for loop } ) { //stuff related to the initial if condition };
I've been working on a program on and off for around a week now and I've been struggling towards the end of the program.First of all, the program is a maths quiz which generates two random numbers per question.I'll give you one part of my code:
Code:
srand ( time(NULL) ); //seeds the random number generator int score = 0; int a = rand()%12 +1; //generates a random num between 1-12 int b = rand()%12 +1; int c = a+b; int d; }
[code]....
I've basically copied the above code 10 times and changed the variables by going through the alphabet e.g.
Code:
int a = rand()%12 +1; //generates a random num between 1-12 int b = rand()%12 +1; int c = a+b; int d; all the way to
Code:
int an = rand()%12 +1; int ao = rand()%12 +1; int ap = rand()%12 +1; int aq = an+ao-ap; int ar;
Now what I'm going to do is remove all the declared variables and create a loop. But my problem is; If I wanted to declare four variables for e.g.
Code:
int a = rand()%12 +1; int b = rand()%12 +1; int c = rand()%12 +1; int d = a+b-c;
Would I place the srand( time(NULL)); inside the loop? it's confusing because I know an example of a basic loop with an array would be:
Code:
#include <stdio.h> #include <conio.h> int main(void) {
int test[5]={21,18,47,21,4}; int I; int total=0;
for (I=0;i<5;i++) total += test[I]; }
[code]....
how or where to include the random number generator in the loop and to make it ask 10 questions at random.
I am writing a program where all work is done in the class methods. Main is used to call the methods. I need to know how to get a loop to work without any variables in main that can be used outside the methods. This is what I have in main:
#include <iostream> #include <string> using namespace std; #include "FerryBoat.h" int main() { //create a constructor for a ferry boat FerryBoat myBoat('B', 20, 'A');
I am making a program to run Fibonacci series. I have created 2 array.
1)- 1st array holds only 0, 1 2)- 2nd array holds other values eg: 1, 2, 3, 5..........etc
I am using while loop to get the febonacci series and storing it in a 2nd array called int[] numbers.
After getting value using while loop, I am joing both the arrays using int[] final = arr.Concat(number).ToArray();
At last, I have used foreach loop to add the febonacci series into the listbox.
The problem I have is that, I cannot able to concat both the arrays. I tried to assign number array at the top of the while loop. so that number variable will be accessible outside the while loop. But I am getting a error.
See the code below
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms;
I'm working on a project that uses type char instead of type int to make selections in a menu that calls functions. I'm really hitting a wall with the while loop, I'm pretty sure my syntax is wrong for type char.
I have the program working but when I check if the input to make sure it is not a char it creates a infinite loop. I used an if statement to check for the issue and solve it but its not working. I even tried throwing an exception but I learned later they are not used for things like this.
Code: #include <iostream> #include <limits> #include "contacts.h" using namespace std; int main()
Write a count controlled loop than can print "i" char. The user is supposed to input a integer and that integer is how many asterisks there is on the blade, in this case it is 5.
* * ** ** **--------------- ******* ** ** ** * ** * -10 Rows high ** -blade always connects on second row of handle ** ** ** **------------------
I have designed a vc++ dll for a controller. I want to add usb plug and play feature inside the dll. I searched on line and came to know:
"If the project is an unmanaged C++ DLL project, then I can only create windows in an unmanaged way, i.e. the usual Win32 API way, such as adding a new dialog box as a resource, or simply using RegisterClassEx() and CreateWindowEx() to create the window yourself, then pump messages for those windows using GetMessage(), TranslateMessage() and DispatchMessage()."
how to use this concept.
I have created a separate application (in delphi 2007) that load this Dll. But I want to add this Plug and Play feature inside me dll.
I need a slider with number displayed inside the slider. Slider thumb or number should be moved and finally i need to fetch the value where the slider thumb is placed. I had attached the image of slider which i required.
I figured it out when I built a simple demo project. Problem arose because of trying to access a c-wrapper dll from the app class whereas the wrapper class had not been initialized there but rather in the main dialog class - so naturally it didn't work!!! Anyway, I've attached the demo for any who might be interested, but I regard the problem as resolved. Shows the value of building simple projects to isolate a problem. I failed to organize the order in which such a program initializes - I guess it's always App first, then MainFrame, then Doc and View (I think).
What is the programmers responsibility with respect to const char * returned by various functions, like the C++ string class c_str() function which returns a const char * to an c style string array? In VC++ I cannot delete a const char * which holds a string literal. Take the following code for example:
Code: void func() //a useless function with illustrative code { string s1("abcd"); string s2("efgh"); const char * cc1 = s1.c_str(); //c_str() returns a const char * c style string pointer s2.c_str(); //this returns a const char *, which must be allocated on the heap right? delete cc1; //produces run time error in Release mode in VC++ }
The problem with the above code snip is that space is allocated on the heap (or so I believe) for the const char *'s returned by the 2 calls to c_str(). The delete attempt fails and there is no opportunity to delete the space allocated by const char * because its not assigned to anything (however I see c_str() used this way extensively)
So, if I cannot delete a const char *, how does the memory get recovered? Perhaps the string objects s1 and s2 themselves have pointers to the items on the heap made by c_str() calls and they get deleted by the destructors of s1 and s2 when the function ends?
The characters show up in the list box as short unreadable characters. like it is chopped.
If i change to : Sendmessage(hndl, listboxupdate,0 , (LPARAM)&buf[15]);
Then I can see readable valid strings of up to 50 characters and then empty unreadable characters afterwards. I tried all kinds of things , including using CString, still did not work.
