I usually check if a bit is set using:
Code: bit = (number >> n) & 1; where `n` is the bit I want to check...
But I came across a stackoverflow answer saying:
bit = number & (1 << x); will not put the value of bit x into bit unless bit has type _Bool (<stdbool.h>).
Otherwise, bit = !!(number & (1 << x)); will..
So why is this? why the double !?
I'm getting a stack overflow error because for large numbers, this code I'm working on allocates too much on the stack.
Is there a way of tracking stack allocations specifically?
Will multithreading solve my problem if each thread is doing the static allocations?
Would I really have to use malloc or new every time I wanted to use memory just to make my code scale to huge numbers?
Here is my error message: Warning1warning C4717: 'getx' : recursive on all control paths, function will cause runtime stack overflow
and here is my code I will Bold the part that is giving me problems!
class point
{
public:
point();
[Code]....
After not programming for sometimes I decided to program a small application. But I have some trouble according to what I remember and re-checking arrays online. I don't understand how the code I wrote below is possible, shouldn't give a stack overflow error or something to that extent? Instead it gives me the value of 3.
#include "stdafx.h"
#include<iostream>
int _tmain(int argc, _TCHAR* argv[]) {
int arr2 [2];
arr2 [3] = 3;
[Code] ....
I'm pretty new to C, and keep getting an error. Basically I'm trying to convert a ppm image to all red. Here is my code that I can't get to work:
Code:
change(pixel_t *PIXEL, &w, &h,pixel_t *buffer);
And here is the beginning of my convert function:
Code:
void change(pixel_t *pixel, int w, int h, pixel_t *buffer) {
int average, sum;
int i;
pixel_t *pointer;
Everything else works fine. I keep getting an error when I call the convert function. It says "expected expression before pixel_t" and "too few arguments to function "change". I know that everything else in the main is working.
I am trying to implement the insert function of a binary tree. Atm when I try and insert 3 nodes, the program breaks and gives me a stack overflow error. The error points to a getter function for an identifier for the data in my node class.
void LinkedList::add(Product *myProduct) {
if (_length==0) {
_head = new Node(NULL, NULL, myProduct);
_end = _head;
_length=1;
[Code] ....
Here is my insert function, the error message is
"An unhandled exception of type 'System.NullReferenceException' occurred in SDI2.exe
Additional information: Object reference not set to an instance of an object. "
In my main I have declared an instance of product, "productToAdd = new Product(id,idPrice);" so I'm a bit confused as to what I need to include..
I had a quick question about how to check the balance of brackets in an HTML file using a stack (pushing and popping). I understand pushing and popping. I get lost when it comes to the logic of having to actually check what is in the brackets, and making sure those are nested correctly.
So while
<title><b> THIS FILE </b> USES CORRECTLY NESTED TAGS </title>
is correct and
<title> <b> THIS FILE </title> IS </b> NOT NESTED CORRECTLY.
is incorrect;
How do I check for the actual tags inside the brackets, keeping in mind that there are single sided tags as well.
(ex. <img src="a.jpg"/>)
I was just wondering how to deal with overflow. My code works for exponential when i put small numbers in like 2 and 3. So it would do 2^3 which would be 8. But if i try something like 2^44 then I just get 0.
View 2 Replies View RelatedCode:
char buffer1[10];
char buffer2[10] = "something";
sprintf(buffer1, "with %s", buffer2);
In a statement like the one above, is there a threat/leak or does it only truncate the string that is loaded into buffer1?
Small code to show overflow...But when I compile and run - buffer_one is not being overwritten when the byte size of buffer_two overflows .
Code:
#include <stdio.h>#include <string.h>
int main(int argc, char *argv[]) {
int value = 5;
char buffer_one[8], buffer_two[8];
strcpy(buffer_two, "two"); //Put "one" into buffer_one
strcpy(buffer_one, "one"); //Put "two" into buffer_two
}
[code]....
I am performing arithmetic operations on very large integers that operate around the threshold of the maximum positive integer an int variable can handle (i.e. 2147483647) for a 32-bit machine. I have been studying the in-built functions in the C++ Standard Library for some time now where I came across some error detecting functions in the <cmath> and <cerrno> header files. The impression I got from the literature is that they are solely used in conjunction with functions contained in the <cmath> header file and not necessarily with fundamental arithmetic operations like addition and subtraction.
I need a means to know when my arithmetic operations generate overflows/underflows! Is there any way I can adapt the functionalities of these functions to my needs?
preventing a buffer overflow when dealing with strings being passed as arguments.
If I have a function prototype such as:
Code:
void foobar(char *bar);
That argument bar - is intended to take a pointer to a buffer of x characters in length. Inside that function, I can't get the size of that buffer, as bar is now just a pointer to a char. I COULD just make the user of this function pass a length parameter, but there is no guarantee that would be correct. Is there a bullet proof way of detecting that the user has provided a buffer that is too small?
Why I have a
HTML Code:
FLOATING POINT ERROR: OVERFLOW
ABNORMAL PROGRAM TERMINATION
in the code below?
Code:
#include<stdio.h>
#include <math.h>
#include<conio.h>
#define A 0
#define B 1
float F(float x0, float y0) {
return (0.2*x0)+(y0*y0);
[Code] .....
What is wrong with this code? I keep getting
HTML Code:
FLOATING POINT ERROR: OVERFLOW
ABNORMAL PROGRAM TERMINATION
Code:
#include<stdio.h>
#include<math.h>
#include<conio.h>
#include<iostream.h>
#define N 4
float x[5]={0, 1, 2, 3, 4};
float y[5]={0.5, 2, 7.5, 20, 42.5};
[Code] ....
Everything seems to be correct from my perspective. heres the program: Code: /*c program to check whether a string is palindrome or not*/
#include<stdio.h>
#include<string.h>
int main(void) {
char str[30];
int i,j,flag=0;
[Code] .....
The reason being is that it says that my program is right
Code:
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#define NFlights 10
struct date {
int month;
int day;
int year;
int hour;
int minute;
[Code] ....
Q. In context of C language syntax checking, which of the following can be modeled using Finite Automata?
(A) Detecting proper termination of an instruction.
(B) Detecting balance of parentheses.
(C) Detecting initialization of a variable.
(D) None of the above.
I am new to C++ , i want to know how to check if a key with modifier is pressed.
When I use GetAsyncKeyState() it gives me error identifier not found.
I think I may have found a new way of checking for 3d polygon collisions, but I'm not sure. The method involves...
1. finding the planes that the primitives lie on
2. finding the line where the planes intersect
3. if both polys have points on both sides of the line AND have points that overlap on the 1d space of the line, then they intersect.
I have some half done code testing this, and so far it seems to be sound and fairly fast. These are some average time-tests done on my machine for each part:
1. 30 microseconds (both)
2. 7 microseconds
3. TBD
I have a question, how can I check if a program is running using c++? For example
if (notepad.exe is running) {
.... ..... ....
How would I go about checking for deallocated memory?
For example, let's take this into consideration:
// Unsigned 32-bit / 64-bit integer: uint32, uint64
uint32* Pointer = new uint32[ Size ];
uint64 MemAddr = ( uint64 ) Pointer;
delete[] Pointer;
The above code would proceed to create a new array, store it in a pointer and retrieve the memory address of the array before finally deleting the array.
So let's assume we re-build the pointer and try to access the now deallocated array:
Pointer = ( uint32* ) MemAddr;
Pointer[ 0 ] = 0;
Based on the above snippets of code, how would I check "Pointer" after rebuilding the memory to check if the rebuilt memory has actually been deallocated. Without a check we'd get an exception error.
A bit of detail on why I am trying this:
Before thinking up how to do this, I was storing the addresses in a list and check the list for the addresses to see if they existed or not. However this requires an O(n) search, which isn't exactly what I am wanting. So instead if I used a check for deallocation method, I can go for an O(1) time check and reduce the total time it would take to check for memory allocation/deallocation.
I have created a prompt which prompts the user for an integer and I have set up a loop to check for if it is an integer or not. My "bug" is that a user can enter an "integer" and "space" and "enter" and it does not give any error and assumes that "All is FINE!". I have gotten the value from the ascii table of 'SPACE' and put it as a check in my parameter of while, but it does not work.
Here is my code:
int x, y, boolean, i;
char buff[256];
printf("Enter the first integer value: ");
scanf("%s", buff);
i = 0;
boolean = 0; //initializing our boolean var that will eventually decide if we have an error or not
[code]....
Suppose you have a templated class, such as
template <typename T>
class Matrix {
// some stuff and some methods
};
and let's say that you have some methods that need to do some type-dependent stuff, like, for example,
template <typename T>
Matrix<T> Matrix<T>::transpose() const {
// get this->rowCount, this->columnCount
// create a Matrix that has rowCount amount of columns and columnCount amount of rows
// copy (*this)[j][k] to theMatrix[k][j] (for all of the entries in *this)
// if the entries are complex, take the complex conjugate of them all
}
Would it be good practice to check explicitly for the typename parameter (or is this, somehow, defeating the purpose of templates)? std::cout << "I know that this is a design question, but it needs to be asked... ";
I'm playing around with parts of code and am coming across some errors. Most of my concern is related to strtok(). I've used it before but with a char* named token. I used a while loop to continuously check whether token was equal to NULL. In the following code, however, there aren't any checks. I was wondering if that is why this code prints (null) while running. Also, I would like to know if it is possible to read input like this code attempts to do - assigning tokens to each variable one after the other.
The format of the input:
Zucchini, Squash, pound
Yellow, Squash, pound
Tomatoes, Ugly Ripe, each
#include <stdio.h>
#include <stdlib.h>
[code]....
Assuming I have a list of pointers to a generic type T:
#include <vector>
//...
list<T*> myList;
Now assuming I want to go on the list, and if T's type is matched to the type I'm looking for, then cast it to this type and do something. List shown here:
list<T*>:: const_iterator iter= myList.begin();
for(; iter!=myList.end(); ++iter){
if( typeid(*iter)==typeid(Something*)) //RUN-TIME ERROR
dynamic_cast<Something*>(*iter)->DoSomething();
}
how do I fix this run-time error?
#include <iostream>
using namespace std;
int main(){
int x;
cout << "Enter character:";
cin >> x;
[Code] ....
If i type in:
+
How come it says that "this is not addition?