C/C++ :: Possible To Append Numbers To The End Of Variable Names During Runtime?
Dec 6, 2012
I am trying to write a program that would convert numbers of base 10, decimal numbers, to binary or hexidecimal numbers, base 2 and base 16. I want the program to run a loop through the various numbers input and store each number converted to the new type in a separate variable with the same basic name but different last letters/digits to differentiate between them and add them to the total.
Basically, I'm saying that i have the user input a number and letters. Let's say 15, d, b. So they want to convert 15 of decimal type to binary.
The program would then take the variable used to hold that number, and the other to variables to decide what function to perform on the number.
Then I will already have a variable initialized for the 3 possible conversions (binaryKey[], decimalKey[], hexideciKey[])
Then I want it to convert it and store the number at different places in the array to form the final number. Although, there is no way to predict what number the user will input, so there is no way of knowing initially where the converted place-value will need to be placed in the array.
I was wondering if there was a way to have the program run a loop where as the progression continues, it appends a number to the end of a universal name for the variables and then adds them together in the correct order creating the sequence that means that number.
In simpler terms:
Input a number: 15
Input type of base: d
Input converted type: b
Program then continually divides the number by 2, storing the remainder in a new variable
Such as: for(int i=1, i < (str(number).len), i++){
when i = 1, you would get
int number1;
Depending on the message ID different messages represent different values for one project.For example msg with ID 10 can include in the 8 bytes something like:
Printing the message is no big deal. But here comes the tricky part. I want to print out the specific information hidden in the 8 bytes. I can define the structures for every msg ID and compile the program with this "special" header file, but I want to do it during runtime of the program, loading the information regarding the msgs, because i can have different projects where the information for different msg IDs can differ.
I've a non-C file, where basically all the information is written. Lets stay frame named
GetStatus{ bit 0 - 7 width bit 8 - 15 height . . } etc.
How to read it on runtime and decode the messages? On runtime I'm not able to create variables and structures anymore!
I want to ask for a number as an input during runtime and then create an 2-dimensional array of size as specified by user. i.e. if the user inputs 3, the array should be of size 3X3, and likewise...
Under visual studio, this is a typical run time error,
Code: void func(int x){ x = 3; } int main() { int x; func(x); }
When x is passed to the function func, it is not initialized. But my question is that why it should be an error? On the other hand, if I change the definition of func a little bit like this,
Code: void func(int& x) { *x = 3; } int main() { int x; func(&x); }
Now in main, x is still not initialized, but this time there isn't a run time error like "the variable is being used without being initialized. Why?
I haven't tried to run my program yet, but maybe I will save some trouble if I ask this question first.I am using MC PIC16F690, and I could make a pin high or low by writing RCx = 1 or 0, where x is the pin in the C port. However, I want to use the counter variable from a for() loop as the pin number. Will RC(variablename) = 1 work, or is there another syntax?
I am looking at some C++ code that has many variables that start with underscores. Why? What's the point? I know in Python its a way to keep them private, but I don't understand why we would do that in C++ when we can just make something private.
For my project I have to sort 5 numbers and 5 names using a template bubble sort. I have one header for the numbers, and one for the names. This is what I have so far for my testing page:
#include "Floatheader.h" #include "Nameheader.h" #include <string> int main () myFloat obj1; myFloat obj2( 2.2, 5.1);
[Code] .....
I have to create a template to look like this: template<>....with a class inside the arrows. Then, I have to use bubble sort to sort the 5 names and number objects I have created. Sorting the names and numbers and also using templates?
I have a dataset which is a coauthorship network (a .txt file).I want to replace all the names of the authors with a unique number(no matter what the number is but it's important these numbers should be unique).
I've opened the dataset in excel then copy the author's names to another excel file,then I want to replace the authors names with their row numbers. what should i do?
i have a vector of stores. i would like to delete the specified choice(store) from the list. Here is what i have but my erase statement is wrong and wont compile.
void Store::deleteSpecifiedStoreFromList(string choice) { for (int i = 0; i < this->stores.size(); i++) { if(this->stores[i].getStoreNames() == choice) { this->stores.erase( std::remove_if( this->stores.begin(), this->stores.end(), choice ), this->stores.end() ); } } }
I want to have the random numbers between 1 to 5 for a variable of 5arrays. for having the random numbers i am using the code as below.
Code: for(int i=1;i<=5;i++) { int j=rand()%5; cout<<j<<endl; }
The problem with this way of generating random number is that i get the same set of random numbers in every outputs. Is there any other way to have different random numbers with many different outcomes as much as possible.
I am trying to keep a count on a variable name stored within a structure as char*'s. They are of the same field and I do not know how many there will be so I would like to keep a standard name and append the count.
So say I have a variable name such as "desk", but as I have many of these said desks so I would like to call them "desk1", "desk2", "desk3" and so forth. Any recommendations on how I could do this?
Also since this is somewhat relevant is there an easy way to convert from an integer to a string, something that would work like atoi() in reverse? I wouldn't mind writing a method to do so myself but haven't a clue as to how.
I am trying to understand how to append some code to a text file. I have run a simple program like the one below. Basically it opens a text file and then it appends the string aaaaaaaaaa
How do I go about doing this? The problem I am experiencing is that all the / and " characters in the above snippet of code seems to get the C compiler confused. One thought I had was to create a string like the one below but as I mentioned, the number 0 in the code is surrpunded by " " and this confuses the compiler:
Dynamic memory allocation and pointer arithmetic with char arrays.
The class was given to me in a very basic skeleton form with prototypes but no implementations, along with a test function to test my implementations. I CAN NOT use any C String functions in this assignment.
The part of the program which is troubling is the append function, which just appends a parameter string215 object to the end of the current string215 object.
// Add a suffix to the end of this string. Allocates and frees memory. void string215::append(const string215 &suffix) { char *output = new char[str_len(data)+suffix.length()+1]; for(int x = 0; x < str_len(data); x++) { *output = *data;
[Code]...
This portion of the code is tested in the 13th test of the test function as shown here:
string215 str("testing"); ...
// Test 13: test that append works in a simple case. curr_test++; string215 suffix("123"); str.append(suffix); if (strcmp(str.c_str(), "testing123") != 0) { cerr << "Test " << curr_test << " failed." << endl; failed++; }
Here is the description of the append class: Add the suffix to the end of this string. Allocates a new, larger, array; copies the old contents, followed by the suffix, to the new array; then frees the old array and updates the pointer to the new one.
My program aborts at the very end of the append function execution with the error message:
I was recently introduced to the fstream header file. I want to know is their a easy way to print an output with append data in a .txt file.
And secondly I am also having an error with my header file. It says error: cannot open source file "fstring" when I hover my mouse over "#Include<fstring>".
I'm trying append more characters to a txt file after write title of foreground window and a newline character, but after first character, the next appear after a newline. Here is result => [URL].... and here is my code:
I'm trying to append data to a CFile using FILE* But when execute the application, it always give error saying "No such file or directory". I can actually see the file created but it just keep giving error "No such file or directory".
Is the file being lock or the file just created so it can not be find by fstream(FILE*)? or the file mode is wrong?
Attached is the printscreen of the FILE* pointer. the pointer is evaluated as bad pointer. Why the FILE* pointer not able point to the file being created?
Trying to append a comma to a string. Getting "Segmentation Error" on Solaris when the function is entered the second time.
Code:
// Appends a comma to the given string void appendComma(char* instring) { if (instring == NULL) { instring = realloc(NULL, strlen(",")); strcpy(instring,",");
