I want to give a try to "restrict" type-qualifier. I have looked for examples on google and I see the format is used: "int * restrict p";
However when I write this I get an error: "p is undeclared"
I am using GNU GCC Compiler with Code::Blocks.
How can I solve this problem. Is it possible me to adapt the compiler to C99 standarts, if I can, will it solve my problem?
Is there a difference in member functions depending on whether they are defined with a qualified ID? For example:
class test {
public:
int foo()//defined here {
return 0;
} int bar();
};
int test::bar() {
return 0;
}
Is there a difference in foo and bar other than their names?
Assume the user has already put in the number of students (hence my variables numStuds, which will most likely be irrelevant to my problem).
So suppose I have this:
void inputStudentInfo(string *names, int *movies, const int numStuds) {
for(int i =0; i < numStuds; i++) {
cout << "Enter student name: "; getline(cin, names[i]); read_string(names[i]);
[Code] ....
Then I have my data type checking function:
//Data-Type Checking for strings
string read_string(string Sname) {
while(!cin.good())
[Code] ....
I am getting errors. I know the problem I think is that I am trying to data type check for a string made up of pointers* with just a string but I don't know how I am supposed to check this?
I think I need to use
Code:
while(input[0]!='
'){
scanf("%s", input)
printf("%s", pointerhere);
}
basically we were asked to make a program that will print everything before the user hits the enter button. we cannot use fgets and we have to use pointers here.
not sure what exactly to do. We were told not to use fgets cause it's so easy and we need to incorporate pointers in this project..
I always have confusions while using pointers with functions both as arguments and as return type.
View 1 Replies View RelatedI have screen scrolling up and running but it keeps going after the background finishes. how do you fix that?
View 4 Replies View RelatedI'm doing error checks in C and I'd like to know how to restrict the input of a string to 2 letters and if it is exceeded, i'd like to loop and ask for the code to be re-entered.
Code:
for (i = 0; i < code7; i++)
{
printf("Enter number of items: ");
scanf("%d", &item_qty[i]);
[Code].....
I am trying to write up something to have a user to enter a four digit number. Only four digits, Ex: 0001, 0116, or 9999. There is no getting around the selection 0001 or 0002. I understand if not done correctly, the first three 0's will be ignored.
I've been just playing around with what I have below but I just don't remember how to do it nor can I find a good example online to figure it out. I know it is not correct just typing to try to remember. I am aware that it is gibberish right now, this is just me brainstorming.
int number;
cout<<("Please enter the four digit number(Ex: 0001):
");
cin>> setw(2) >> number;
cout<<)"Please enter four digit date. Two digits for month and two digits for year:
");
cin>> date;
if (number< || number > 30)
cout << "Invalid choice. Try again." << endl;
cin.clear();
I was creating a template and I realized that certain data-types/structs/classes would not be applicable to my template.This would cause bugs and errors if used incorrectly. Is there a way to restrict a template-capture to certain types/classes?
View 2 Replies View RelatedI have one requirement. I have a project lets Say baseProject.vcxproj. It has some header files. Another project lets say dependentProject.vcxproj loads baseProjects's dll and uses some of its header files.
When some other project lets say unrelatedProejct includes the header file from e dependentproject which includes baseproject's header file. It makes to change the include driectory setting of unrelatedproject. How to avoid this.?
baseproject
base.h
{
}
dependentProject
dependent.h
[Code] .....
I have to write a program for class in which users will be inputting:
start time = startTime
number of minutes = callDuration
so first off, teacher wants us to input time as a floating point number such as 09.00
How do I validate the time so that users cant input i.e. 09.61 for every hour? In other words, so the user cant input minutes 60-99 for every hour.
then, when calculating:
endTime = startTime + callDuration
how would I make endTime display a correct time in such a situation: endTime = 09.45 + 00.30
so that it displays 10.15 not 09.75
I'm trying to create an array of pointers to pointers which will point to array of pointers (to strings) I tried
Code:
int i;
char *string[]={
"my name is dave",
"we like to dance together",
"sunny day",
"hello",
[code]...
the app keeps crashing , I don't know how to make the array-elements to point to another array-elements..
I am a little confused while comparing char pointers to integer pointers. Here is the problem:
Consider the following statement;
char *ptr = "Hello";
char cArr[] = "Hello";
When I do cout << ptr; it prints Hello, same is the case with the statement
cout << cArr;
As ptr and cArr are pointers, they should print addresses rather than contents, but if I have an interger array i.e.
int iArr[] = {1, 2, 3};
If I cout << iArr; it displays the expected result(i.e. prints address) but pointers to character array while outputting doesn't show the address but shows the contents, Why??
I'm having some problems with changing an array of numbers of type char to type int. Every time i try to sum 2 array indexed values it returns some letter or symbol. Also, if i change the type of the array in the functions the compiler gives me an error message. I would also like to add that the problem requires that the first two arrays be char so each individual number gets assigned to a different value.
My current code is:
Code:
#include <iostream>
void input(char a[], char b[], int& size_a, int& size_b);
void convert(char a[], int size);
void reverse(char a[], int size);
void add(char a[], char b[], int c[], int size);
int main()
[Code]....
how to convert an element of int type of an array to char type?
View 2 Replies View RelatedI have a function like this:
template<typename T>
void f() {
//...
[Code]....
list contains, in order: A, B and C in any order, D, E
I am thinking it is possible with some clever template and polymorphism combos, but maybe not. As a last resort I know how to make it work by storing static type information in each class, but I'd like to avoid that if possible.
I need to use the type RectangleF as a built in type in c++ ie I need to declare a variable rect as RectangleF rect;
what do I have to include to be able to do this.
Let me put it into the code snippet:
/**
This class build the singleton design pattern.
Here you have full control over construction and deconstruction of the object.
*/
template<class T>
class Singleton
[Code]....
I am getting error at the assertion points when i call to the class as follows:
osgOpenCL::Context *cxt = osgOpenCL::Singleton<osgOpenCL::Context>::getPtr();
I tried commenting assertion statements and then the debugger just exits at the point where getPtr() is called.
I'm trying to write a function that takes a 32bit address and a data to store at this address.
I'm wanting to take the 32 bit memory address eg 0x12345678 and split it
into 4 x 2 bytes
12, 34, 56, 78
then each of the 4 entries is at most a 256 entry array.eg
FF, FF, FF, FF
So in this example, 0x12 points to 0x34 in the second array, which points to 0x56 in the third array, which finally points to 0x78 in the last array. This last array holds the actual data.
After successfully doing 0x12345678, say I might get a read for 0x1234AABB. So, the first and second pointers already exist, but I then have to create and write to dynamically created arrays.
The arrays need to have all entries set to NULL so that i know whether to follow the pointers to overwrite a previously entered value or create new arrays and pointers.
It all looks good and simple in the pseudo code I've written up but I'm having trouble coding it. I'm currently trying to deal with the first entry case, ie all array elements are NULL, but I'm getting confused with the pointers and creation of new arrays.
void cpu::store(unsigned int mem_add,unsigned int mem_val) {
int first = (mem_address&4278190080)>>24;
int second = (mem_address&16711680)>>16;
int third = (mem_address&65280)>>8;
int fourth= (mem_address&255);
[Code] .....
A1 has been declared as
int* A1[256] ;
How to change an enum type variable to a string type variable?
View 2 Replies View Relatedgive me a few solid examples for when one should use pointers.
View 14 Replies View RelatedThe first sample program that I am reading on the book has the following code:
Code:
* Demonstrates basic pointer use. */
#include <stdio.h>
/* Declare and initialize an int variable */
int var = 1;
}
[code]....
Is this a compiler error or is there a proper syntax for pointers using the gcc compiler?
So when if you want to change the values themselves for example in an array (just for example) this is valid;
void test(int* test)
{
test[0] += 10;
}
int bob[] {1, 3, 5};
If you did that bob[0] would not equal 11. All well and good right?
Now if you do this?
int sally = 33;
test(sallay);
This wouldn't work at all you actually have to use
void test(int& test)
{
test += 10;
}
how the memory addresses etc. are working here? I don't understand why you need to use & the reference operator if it's not an array? Why wouldn't that still work?
Alright, after what seems like forever I'm on the last stage of modifying my Payroll Program. This time I have to sort using pointers and I only have to sort the Net Pay category.
Using one of my earlier programs I've removed content from it until it's in a state where it runs but contains no sorting functions.
So now I've to a working program that lacks any kind of sorting and looks like this.
#include <iostream>
#include <fstream>//file input output stream
#include <iomanip>
#include <string>
using namespace std;
//function prototypes
int readalldata(long int id[], string fname[], string lname[], int hoursworked[], float hourlyrate[], int n);
[Code] .....
My hints for how to add pointers to the program are...
int *np,tmp;
for (i=0,i<n; i++) np=&netpay[i]; //associating the netpay to np;
temp=np[i];//storing the pointer to a temp
I've been fooling around trying to sort the Net Pay by pointers using these hints for a bit now and I'm still not getting it.
I have a problem. I want to set pointers to a default value for both 32 bit and 64 bit compiles. The 32-bit version works as:
enum constants { UNDEFINED = 0xDeadBeef }
if ((unsigned long)ptr == UNDEFINED)
but I can't seem to extend this to 64-bits. I've tried
#if __SIZEOF_POINTER__ == 4
enum constants { UNDEFDATA = 0xDeadBeef };
}; // enum constants
#elif __SIZEOF_POINTER__ == 8
enum constants { UNDEFDATA = 0xDeadBeefDeadBeef };
#endif
with:
if (ptr == UNDEFINED)
but get a message saying the '==' is undefined (I understand this)
Is there any way to setup so that I can change the size of my constants so that the comparisons will always work correctly? I've tried a 'typedef' but the compiler complains at
'typedef unsigned long long ADDR' // won't accept, and
static const SlipCellBase * const TEMPORARY = (SlipCellBase&)0xFFFFFFFFFFFFFFFF; // illegal conversion
enum doesn't work (because it's an int?)
What the second print statement prints
main() {
struct s1{
char *str;
int i;
struct s1 *ptr;
[Code] .....
I executed the code and the output was some number(for second printf) but it should print a string.