I'd like to do something like this:
private List<Vector2> myVectors = new List<Vector2>();
private List[] myListOfListsOfVectors = new List[10];
for (int i = 0; i < 10; i++){
myListOfListsOfVectors.Add(myVectors);
}
Or better yet, if I can create 10 lists called "myVectors" and access their objects by "myVectors[1][objectIndex];"
This problem is best explained by looking at its output below. I stored 15 different values but when retrieved some are wrong.
#include <iostream>
using namespace std;
class A {
public:
int ** pointer;
[Code] ....
I need to store and retrieve the 15 different values correctly. How to solve this? The main thing is, I need to store the pointer in class A objects.
I've been trying to store the inital size of a list in an int variable, so I can access it later in case I modify the list size. For example, I did the following:
std::list<AType *> myList;
myList.push_back(anATypeobject);
int initListSize = myList.size(); //initial list size
myList.push_back(anotherATypeobject);
myList.push_back(yetanotherATypeobject);
while(myList.size > initListSize)
myList.pop_back();
What this is supposed to do is to get an initial size of a list, and then be able to return to that initial size. However, when I try to do it in my code, initListSize always change if myList.size() changes. Is there a way to change that?
I am trying to query an Informix database using a List<T> collection's elements as variables. I can build the list and connect to the database, but I am unsure how to iterate through the list and query the database for each item in the collection.
My list is of type string, and contains Order Numbers. I want to query item information for each order number in the list.
I'm trying to run so called student-administration program.I got functions that can read and write student data, but the one saving the data from about 30 students has some problem that I can't figure. (warning: I'm quite new to C programming)so this is the code:..I guess I can't use global variables as function arguments?
Code:
//global variables
static char ReturnName[31];
static char ReturnFirstName[31];
static float ReturnAverage;
}
[code]....
incompatible types when assigning to type 'char[31]' from type 'int'
I am getting and infinite loop for loop pointer variable current which points to head and is incremented by current->next in while loop. I use the pointer variable the same way in my display routine and it works. Here is listing of code.
#include "stdafx.h"
#include<iostream>
struct node{
int data;
node *next;
[Code] .....
I finished my project and it does work, but every time I hit enter to end the program I get an error that says my variable array is corrupted.
here is my code:
#include <iostream>
#include <ctime>
using namespace std;
int main() {
system ("color C");
[Code] ....
How could I stop this end error from occurring?
How do I insert a array size as variable?
View 5 Replies View RelatedI have a simple problem about memory allocation.In the function Nr_elements() i assign a value which represent the elements of array. The pointer p is initialised with the address of variable n, but when i compile i dont know why but dont work. This function return a pointer.
Code:
#include<stdio.h>
#include<stdlib.h>
int *Nr_elements();
int *allocate(int);
void deallocate(int *);
[code]....
This code snippet compiles and runs fine
Code:
#include <stdio.h>
int main(void) {
int i, a[i];
i=2;
for(int n=0; n<=i; n++)
a[n]=0;
[Code] .....
It prints out 3 "0", but when slightly changed
Code:
#include <stdio.h>
int main(void) {
int i, a[i];
i=200;
for(int n=0; n<=i; n++)
[Code] ....
It compiles fine but core dumps when run, how come? i'm using gcc version 4.4.7, and compiling like this
gcc -std=c99 test.c -o test
I am trying to read a tab delimited file containing 8 columns and store each element of the column as an 1-dimensional array. Though the program prints the strings correctly as in the commented printf but it doesn't give me first_col[0] value and so on. My code is as follows:
Code:
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main() {
FILE *int_file1;
int BUF = 1024;
[Code]...
The inputfile test.txt has the following elements:
34932 13854 13854 2012-01-07
172098 49418 53269 2012-01-07
-
-
-
I am trying to create a global array with user-defined dimensions.the code is:
Code:
int matr_size()
{
int x = 0;
printf("Please enter the number of nodes: ");
scanf( "%d", &x);
printf("There are %d nodes in this simulation.", x);
getchar();
return x;
}
[code]....
I read that an array cannot be defined by a variable in C so I assume that is the issue, but I'm not sure how else to do it. Previously the size was defined by #define NODES and it worked fine but I need this user input.
The WinAPI has a struct like this for raw input:
Code:
typedef struct tagRAWINPUT { RAWINPUTHEADER header;
union {
RAWMOUSE mouse;
RAWKEYBOARD keyboard;
RAWHID hid;
} data;
[code]...
The definition of the struct doesn't show it but the documentation says that bRawData is variable length. sizeof(RAWINPUT) will not be the correct size when the data field is of RAWHID type so how do you allocate a variable with automatic storage type that has the right size for the entire struct? You can get a header that has the size for the entire struct but how do you actually allocate storage space for the data without using malloc? I've seen some example code that used a char array but that violates aliasing rules and there are also alignment issues with that approach.
I am wondering how I could make an array which contains arrays, but with a variable size.My first try..
Code:
int array[][] = {{1}, {2}};
But this isn't proper
I have a function like this
void foo( int i) {
...
uint8_t buf[ i];
...
}
And I don't understand why the compiler is not complaining... I'm using g++ -c -g -Wall to compile ....
I believe that everything is fine except that I can think of the condition can be inserted inside the parentheses ..
#include <iostream>
using namespace std;
int main() {
int i=0, k=0;
char *string_n, **matrix, temp;
[code].....
I have program where i have to check to see if file exist, if it does not then it needs to be created. SO I have a read file that works fine, if th efile exist it reads whats in it, if it does it says the file does not exist. Now Im trying to creata function that creates the file if it doesnt exist. so in my read function when the person enters the name of the file to be checked for..I pass that name to a variable called name..Hoping that I could then pass it into my create file function if it does not exist..and use that variable to pass the name they entered into the createfile array..called filename.. but I am having trouble because i get error when i try to pass from a string name to char array.. even when I change the varialbe name to char, or char [256] it will not work.. I try to fing a way to convert th string to a char using the strncopy function but still no dice..here the code i have for the createfile funciton
void CreateNew(ofstream & FileNew)//Create file
{
char filename[256];
string name;
[Code].....
How can i do this without having to ask the person to enter the file name twice..
I've been working on making a class that makes turning any variable or object into a byte array and vice-versa, quick with minimal pointer interface.
As well as a function for turning any variable or object into a binary text string.
Code:
#include <iostream>
#include <bitset>
#include <sstream>
// Convert a Variable to a Byte Array
template <class var>
unsigned char* VarToBytes(var &data) {
[code].....
I am working in an assignment and part of this assignment is to input a CSV file with floats such as this:
8.5, 10.5, 90.5
49.5, 99 ,97
88, 70, 100
78, 2, 10
into an universal variable array.I just want to figure out a way to simply input the CSV file into a 2D variable array.The values in the array will be later use in functions that I'm trying to figure out but I can't do that until I store these values in the array. I think is just a matter of figuring out how to tell fscanf to ommit spaces and commas, but I don't know how. This is what I have done
Code:
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
float grades[1001][101];
int main(int argc, char* argv[]){
[Code] ....
The output is this
Assignment 1 of student 1 = 8.5 Assignment 2 of student 1 = 10.5 Assignment 3 of student 1 = 0.0 Assignment 1 of student 2 = 90.5
I think I'm close to solve it but something is missing the output should look like this
Assignment 1 of student 1 = 8.5 Assignment 2 of student 1 = 10.5 Assignment 3 of student 1 = 90.5 Assignment 1 of student 2 = 49.5
I am new to C. I've been trying to use C to code some statistical functions originally coded in R. I've encountered an interesting phenomenon. In the function foo1, I declared the array v1v2b using an actual value 1999000. The function runs fine when I call it in R.
Code:
void foo1(double *x, double *y, int *nsamp){
int i, j, k, oper=2, l;
double* v1v2=malloc(sizeof(double)*((*nsamp)*(*nsamp-1)/2 + 1));
outer_pos(x, y, nsamp, &v1v2[0]);
double v1v2b[1999000]; //<-------HERE
for(i=1; i<= 1999000]; i++){
v1v2b[i-1]=1;
} }
However, in foo2, I first create an integer variable called index, and store the value 1999000 in it. I then use it to initialize the same array. When I tried calling this function in R, it either led to a stack overflow error, or completely crashed R.
Code:
void foo2(double *x, double *y, int *nsamp){
int i, j, k, oper=2, l;
double* v1v2=malloc(sizeof(double)*((*nsamp)*(*nsamp-1)/2 + 1));
[Code] .....
I am having following pointer variable declaration
Code: Static double (*funcs[]) (double) = { sin,cos,tan,asin,acos};
Here funcs is an array of pointers to functions which take double as input and gives double as output with static as storage type am I right.
what I need is to get the first integer from a file and assign it to a variable and the others integers to an array. Example: Thats my file content 5 4 6 7 8 0 and that would be the code:
Code:
struct Array{
int n;
int *v;
}
[code]....
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...
View 9 Replies View RelatedI'm expected to get a starting minimum input, and also an ending maximum output (for example: 21, and 25). From here, i have to give output using all the numbers (in a row) between the min and max numbers.
(for the same example:
21
22
23
24
25)
I assumed I would want to create an array using a variable, but i'm not sure of that either.
I am trying to set a variable of type char equal to an element in an array of characters. For example:
char data[4] = "x+1";
char element;
element = data[2];
This seems like a logical progression from number arrays, but when I print both element and data[2], I get data[2] as expected, but element gives a different character every time (I assume a garbage value).
For my default constructor I need to set an array of strings to null and the size variable to 0. Here is my code for that
DynamicStringArray::DynamicStringArray() {
*DynamicArray[]=NULL;
size=0;
}
When I try and compile it I get an "expected primary expression before ']' token" error.