void main() { char str[2][7] = {"1234567", "abcdefg"}; char** p = str; printf("%d\n", *(p+1)); printf("%c\n", *(p+1)); } The output is: 1631008309 5 Edit: Thank you. I see the '5' is only 0x35, other than str[0][4] I supposed to be. Why can't I get out str[0][4] instead of this strange 1631008309?? OMG, I'm foolish...
Hi, I'm calling a C DLL function and need to supply the following C struct: typedef struct { char *mTableId; char **mFieldNames; int mNumFields; char *mFilter; char *mSort; int mOffset; int mMaxRecords; char *mTargetRecordFilter; int mSurroundingRec...
Although I use std::vector almost all the time, I am interested in understanding as much as I can about pointers. Examples of what I am talking about: char* array[5]; // What does it mean? // 1) pointer to an array of 5 elements! // 2) an array of 5 pointers? I am interested in the precise definition of this declaration. ...
Why reference types and pointers are same in compiled code?(You can see in third and fourth line). I tried to figure it out but apparently I could not achieve. If a reference type variable must be initialized at declaration and can not be changed so is there any need to do indirection as in pointers? int x = 10; mov dword ptr...
I have structs like this: struct Child { int foo; char bar[42]; }; struct Parent { long foobar; struct Child ** children; size_t num_children; } I have defined an API like this: struct Parent * ParentAlloc() { struct Parent* ptr = (struct Parent*)calloc(1, sizeof(struct Parent)); ptr->children = (struct Child**)calloc(S...
Hello, I just started using javascript and I'm missing something important in my knowledge. I was hoping you could help me fill in the gap. So the script I'm trying to run is suppose to count the characters in a text field, and update a paragraph to tell the user how many characters they have typed. I have an object called charCounter...
I'm learning c++ and writing a binary search tree. The following is the code I wrote for my insert method. BSTNode * BST::Insert(const std::string & v) { BSTNode *n = !root ? root = new BSTNode(v) : Insert_Helper(v,root); if(n) size++; return n; } BSTNode * BST::Insert_Helper(const std::string & v, BSTNode *n) { if(!n->value.compar...
I am relatively new to C++ programming, but am a C programmer of 10 years so am more comfortable with pointers to objects than I am with references to objects. I'm writing a Solitaire game - is this design unsafe? Is there a better way? Anyway, I have a class SolitaireGame: class SolitaireGame: { public: SolitaireGame( in...
Hi guys, just brushing up on some C for a class and I've run across a little something that makes me scratch me head. For this code: char * findString(const char * s){ /* Allocate space */ char * ret = malloc(strlen(s) + 1); /* Copy characters */ char * n; n = ret; for ( ;*s != 0; s++) if (isLetter(*s)) *n++ = *s; *n = 0; ...
So pray tell, how would I go about getting the largest contiguous string of letters out of a string of garbage in C? Here's an example: char *s = "(2034HEY!!11 th[]thisiswhatwewant44"; Would return... thisiswhatwewant I had this on a quiz the other day...and it drove me nuts (still is) trying to figure it out! UPDATE: My fault...
What makes smartpointers better than normal pointers? ...
Write pointer to string,delete pointer,and load pointer from string? ...
When I read litb answer to this question, I learned that passing an array by reference allows us to obtain its size. I just played little bit with code, and tried to pass a "function" by reference and surprisingly (at least for me), this code compiles: void execute( void (&func)() ) // func is passed by reference! { func(); } Is t...
#include<stdio.h> #include "amicablenumber.h" int i,j; struct amicable { int **amicablePair; int size; }; main() { int startnum = 250; int endnum = 1000; struct amicable* ami; ami = getAmicablePairs(startnum, endnum); printf("{"); for(int i = 0; i<ami->size; i++) { printf("{%d, %d}",ami->amicablePair[i][0], ami->amicab...
Hey fellas... OK, a recent quiz entry tasked the student with writing a method 'longhead' (char *longhead) that would return a string consisting of the concatenation of all of the heads in a given string. Example: char *string = "this"; printf("%s\n", longhead(string)); OUTPUT: tththithis I did come up with a solution, but it works ...
In C programming, you can pass any kind of pointer you like as an argument to free, how does it know the size of the allocated memory to free? Whenever I pass a pointer to some function, I have to also pass the size (ie an array of 10 elements needs to receive 10 as a parameter to know the size of the array), but I do not have to pass th...
Hey everyone, I was wondering if it is possible to traverse a linked list like this: currentNode = randomNode;//where randomNode may or may not = firstNode prevNode = firstNode; while(prevNode != currentNode } Is it possible to do this in C++ when I am trying to find the node before currentNode in a singly linked list? I trying to...
Hey SO, This should be easy for all you C hackers out there :D Anyways, I want to store a 4-byte int in a char array... such that the first 4 locations of the char array are the 4 bytes of the int. Then, I want to pull the int back out of the array... Also, bonus points if someone can give me code for doing this in a loop... IE writi...
In below code snippet, although pointer is not initialized the call is still made successfully temp *ptr; ptr->func2(); Is it due to C++ language property, or it is VC++6 compiler which is foul playing? class temp { public: temp():a(9){} int& func1() { return a; } bool func2(int arg) { if(arg%2==0...
The code is char** p = (char **) malloc(sizeof(char **) * size); //Where size is some valid value. p[1] = (char*) malloc(sizeof(char) * 30); Is the above code fine? My understanding is p -> +---------+ 0 char* + -> {c,o,d,e,\0} +---------+ +---------+ 1 char* + -> {t,o,a,d,\0} //The assignment of these value...