%%.2f needs an extra % symbol to make the final .2f into a format rather than the string literal that’s being displayed. Secondly realloc is intended to resize a previously calloc-ed array in memory. solved Source code using a structure pointer
As the compiler is telling you, this line: Note n = Note(&track.generator); Tries to construct a Note and supply a Generator** to its constructor (since track.generator has type Generator*, &track.generator has type Generator**). However, your Note class constructor accepts a Generator*, not a Generator**. Just do this instead (notice, that copy-initialization is unnecessary here, rather … Read more
A 2D array does not decay to a pointer to a pointer. By using: maxim=findMax((int **)a,m,n); you are forcing the compiler to ignore your error. Instead of int findMax(int **a,int m,int n) use int findMax(int a[][20],int m,int n) and then, call the function simply using: maxim=findMax(a,m,n); You said: The problem statement says that int findMax(int … Read more
Your function is declared to return char and you are returning an array of char. But even if you fix the return value which should be char * it’s still wrong because you should not return a local variable, instead pass the array as an argument to the function like this void n_zeroes(int n, char … Read more
Given your declarations, you need vecP[1]->resize(6); // or vecP[1]->at(3) = 7; The problem being that since your (top level) vector elements are pointers, you need to dereference them to access their contents. The easiest way of dereferencing is to use -> instead of ., as I did above, but you can also use (unary) *. … Read more
Here’s some code which shows what’s going on (in excruciating detail): #include <stdio.h> int main(void) { int a = 11; int b = 20; int x = -1; int y = -1; int *ip1 = &a; int *ip2 = &x; int **ipp = &ip2; printf(“Addresses:\n”); printf(” &a = %p\n”, (void *)&a); printf(” &b = %p\n”, … Read more
If you need to allocate a TEST object dynamically then you can do this: int main(int argc, char * argv[]) { //Just to fill an array with some integers int rows = 3; int cols = 3; TEST* t = new TEST; t->row = rows; t->col = cols; t->a = new int*[rows]; for(int i = … Read more
There’s several problems with your code. First, the swap function doesn’t work. You’re swapping the values of the pointers that are local variables inside the function, you’re not swapping the array elements they point to. You need to indirect through pointers to get the values. int temp1 = *a; *a = *b; *b = temp1; … Read more
It is completely up to the implementation. For example, const data on bare metal ARM uCs is stored in the FLASH memory. You can write to there but it will have no effect at all. Hosted systems will behave differently depending on the OS, its version and hardware. How can I overwrite a const block … Read more
There is none. Once the array-to-pointer conversion happens, the size information is gone. If you need it, you have to pass the size as a separate argument. Since pArr is a pointer, sizeof(pArr) gives the size of the pointer. Your pointers seem to be double the size of ints; that is the case on x86-64, … Read more
Exception thrown at 0x0F640E09 (ucrtbased.dll) in ConsoleApplication5.exe: 0xC0000005: Access violation writing location 0x014C3000? solved Exception thrown at 0x0F640E09 (ucrtbased.dll) in ConsoleApplication5.exe: 0xC0000005: Access violation writing location 0x014C3000?
In your first example, you MUST pass a char pointer for the “%s” modifier so it is actually the way it has to be, you would of course know that if you read the appropriate documentation, like e.g. The C Standard. The second one, is wrong. Because it would invoke undefined behavior. To print the … Read more
Your example code should not give any errors as was proved by Robert Crovella. I looked at your original code and found a misaligned parenthesis cause by that first “for” loop. Good luck… 0 solved CUDA: Using a global thread index with shared memory won’t work [closed]
fix like this #include <stdio.h> #include <stdlib.h> #include <string.h> #define BUFF_SIZE 32 #define STRUCT_SIZE 512 struct info { char name[BUFF_SIZE]; char stAddress[BUFF_SIZE]; char cityAndState[BUFF_SIZE]; char zip[BUFF_SIZE]; }; void selectionSort(struct info *ptrStruct[], int size);//! int main(void){ int count, size;//! char buffer[600]; struct info *ptrStruct[STRUCT_SIZE]; for (count = 0; count < STRUCT_SIZE; count++){ ptrStruct[count] = (struct info*) … Read more
This dereferences an uninitialized pointer, resulting in UB: *p = i; You probably want this instead: p = &i; solved pointer behaviors in c++