I'm trying to insert a structure into a binary file, then read it back out into a "temporary" structure and output some values.
#include <iostream>
#include <fstream>
using namespace std;
struct b_tree_node {
int num_keys; // number of keys in this node
int key_val[3]; // key values (0 to num_keys - 1)
int child[4]; // child file addresses (0 to num_keys)
[Code] ....
I've used qsort to extract the unique student IDs by jumping every four because there's 80 rows of data and twenty students.
I want to make sure it's all working and there's something very strange going on. If you look at my code, when it comes to initialising the structure with the unique student IDs it will happily print them after each one has been initialised inside the for loop (which suggests to me it's obviously done it) but, however, when I want to print them again outside the for loop in another for loop as a "double-check" it goes horribly wrong, presumably they're not in there at all? If you traverse the code to the bottom you'll see my comments.
Now in my for loop, j is going to be incremented 20 times which will correspond to the #define STUDENTS 20. So imagine the array of structure db[j] , the first loop will set i and j both to zero, retrieve the first unique ID and store it in the structure. Then i is incremented by four to acces the next unique ID and then j is incremented by 1 to insert this new ID in the structure.
Code:
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
[Code]....
I'm trying to save a structure to a binary file, then read it out of the binary file into a new structure. I am unsure what is happening but it is not correct.
#include <iostream>
#include <fstream>
using namespace std;
[Code]....
I want to insert an element into binary tree using pointer passing through functions. In my program i have used three structure which are follows :-
Code:
struct tree{
int data1;
struct tree *leftptr;
struct tree *rightptr;
};
struct list{
struct tree **data;
struct list *node;
[Code]...
Here i think problem is in allocating memory to n2 . why i do this because i want to store the address of address of left and right pointers of tree and extract that address to get the address of left and right pointers. Is my method correct ?
I would like to write a complete structure array to a file and read it back, recovering all the data. I have tried the following:
Code:
#include <stdio.h>
#include <string.h>
#define NUM 256
const char *fname="binary.bin";
typedef struct foo_s {
int intA;
int intB;
char string[20];
[Code]...
//---------------------------------------------------- but the mac field is reading back some random value repeatedly. Why is that? And how do I fix this?
A teacher has asked all her students to line up single file according to their first name. For example, in one class Amy will be in front of the line and Yolanda will be at the end.
Write a program that will read in a file of names. Names should be read until there are no more names to be read. Use LineUp.txt as a test file for your program.
Once all the names have been read in display which student will be at the front of the line and which one would be at the end of the line. You may assume that no two students have the same name.
These are the name in the LineUp.txt file if needed:
Cooper
Gavin
Joseph
Sierra
Kacie
Dylan
Kaylee
Will
and so on .....
So i am implementing the class LinkedBinaryTree and i am aplying "Depth and Height" and "A linked structure for binary tree".
#include <iostream>
using namespace std;
// InspectableContainer
template <typename Object>
class InspectableContainer {
public:
int size();
bool isEmpty() const;
[Code] .....
I'm having a problem in my Library assignment, this section of my code is for reading in books saved in a 'book.dat' file on my desktop and inserting them into the linked list. It kind of works, but say if there is two books in the file, it only saves the second book twice.
eg in book.dat:
123 book1 Tolkien 2009 0
111 book2 Rowling 2009 0
So once these are read in, and I call my method displayAll(), it would display the second book twice..
void importFromFile(FILE *fp) {
struct book *aBook;
struct node *aNode;
aBook = (struct book *)malloc(sizeof(struct book));
[Code] .....
Following is the program I wrote it basically takes 9 inputs and then save them into binary file. then print out the data stored in binary data and find inverse of it then print the inverse out. but its stuck in a loop somewhere.
Code:
#include <stdio.h>
int main() {
int a[3][3],i,j;
float determinant=0;
int x;
FILE *fp = fopen ("file.bin", "wb");
[Code] .....
I wonder are there boost available structures that act pretty much the same as binary heaps of C# in VC++?
like this code snippet in C#
Code:
BinaryHeap<Node> OpenList = new BinaryHeap<Node>();
BinaryHeap<Node> ClosedList = new BinaryHeap<Node>();
Code:
namespace LibAStar {
/// <summary>
/// A binary heap, useful for sorting data and priority queues.
/// </summary>
/// <typeparam name="T"><![CDATA[IComparable<T> type of item in the heap]]>.</typeparam>
public class BinaryHeap<T> : ICollection<T> where T : IComparable<T> {
// Constants
[code].....
#include<iostream.h>
#include<conio.h>
class sum {
int a,b,ans;
public:
void geta() {
cin>>a;
[Code] ....
I am trying to run a programme implementing a function with structures in c... which is:
#include<stdio.h>
#include<conio.h>
struct store {
char name[20];
float price;
int quantity;
[Code] .....
I'm writing a function that inserts a row into a matrix and deletes the last row.
But I'm having trouble. What do I need to add to this function:
I have a program that stores values in a map>. I use the map as a dictionary so that I can look through my map if a perticular string already exists. If a string does exist, I want to put the position that I found it at (relative to my text file) in my vector. How do I do this? So far I've tried this:
void mapInsert(string aWordNoSpaces, int index){
// check if word exists in map already, but first we need an iterator object
map<string,vector<unsigned int>>::iterator it;
it = wordMap.find(aWordNoSpaces);
if(it == wordMap.end()){
wordMap.insert(pair<string,vector<unsigned int>>(aWordNoSpaces,index));
[Code]...
Also, why are the zeros showing up here (i've attached a screenshot and circled them): [URL]...
When I tried to run my code I keep getting a "Segmentation fault".
I am trying to write a code that read from a file and put the data into a structure.
The file look like the following:
2001,ABBIGAEL,5
1994,ABBIGAIL,5
1996,ABBIGAIL,8
1997,ABBIGAIL,13
The file have 31 lines.
Code:
#include <stdio.h>
#include <string.h>
int main() {
/* Define a daydata structure */
typedef struct {
[Code]....
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>
#define MAX 200
[Code] .....
I made a txt file which contains a necessary information into my project file and tried to read and print it. However, seems like my program is not reading my file at allI named my file as student
Why doesn't this compile?
struct hi(){
void other();
}histructure;
void hi::other(){
std::cout << "Hi!" << std::endl;
[Code] ....
Makes no sense the structure is written before the structure member function is called so why is there compile errors ??...
I have a pointer to a C string that contains multiple lines of text. I need to change a few characters in the string (possibly adding 1-2 extra). At the moment my code looks like this (char **objectData is the pointer):
Code:
char temp[350];
char* end = strstr (*objectData, "word_before_data_changes");
strncpy (temp, *objectData, 39); // Copying the first 39 symbols
strncat (temp, "6-11", 4); // inputting some data
strncat (temp, end, 100); // copying the last symbols.
I don't know how many there would be. Tried sizeof(end), but this cropped off last two lines for some reason. So using 100 at the moment. This sort of works, but I think it also adds some new lines or null-terminating characters in the end or something like that, because data parser cannot parse the modified data after that.
I have a problem with entering math functions in my Bisection method algorithm program. I just don't know how can I make the function that I enter in my GUI app to go from the GUI to the loop and find the root.As far as I googled I only find codes that you need to pre-enter a function in the double/float.
For example:I have a function f(x) = x^3 - cos(x) - x - 3; and I want to enter that function trough the GUI i made in c++..So this is the main code.
#include "bisection.h"
#include "ui_bisection.h"
#include <QFile>
#include <QString>
#include <math.h>
#include <algorithm>
bisection::bisection(QWidget *parent) :
[code]....
#include<iostream>
#include<vector>
#include<map>
using namespace std;
class foo {
struct type {
int i;
string s;
}y;
[Code] ....
In the sample code
1) why can't we use union if its members have constructors
2) I am not able to insert in Map.
3) also I am not able to use object of struct type y to assign value of its members and later push_back in vector
I am getting following error
knils@knils-HP:scott_mayers$ g++ vector_of_struct.cpp
vector_of_struct.cpp: In member function ‘void foo::fun() const’:
[Code] ....
#include "stdio.h"
char t[16] = {0x8F,0x78, 0xC6, 0x12, 0xBA,0x98, 0xA2,0x16, 0x8F,0x78, 0xC6, 0x12, 0xBA, 0x98, 0xA2, 0x16} ;
char w[44];
void main(){
for(int i=0 ; i<4 ; i++){
w[i] = (t[4*i], t[4*i+1], t[4*i+2], t[4*i+3]);
printf("%0x ",w[i]);
}
}
i want to put some elements of the t array into the w array but when i do this, it prints only t[4*i+3]
i want the output to be something like this
w[0] = t[4*i], t[4*i+1], t[4*i+2], t[4*i+3] = 0x8F,0x78, 0xC6, 0x12
w[1] = 0xBA,0x98, 0xA2,0x16
and so on
How to structure the input of one .dat file and outputting into another one. I have to loop through a file structured "doe, john, 1500", check for errors and then increase the mp by 50. You also have to do this through using a person class too. I think I need to use a while loop to go to eof and use getline to input correctly, but im not sure how to structure it.
Data file:
Horowitz,Jake,1200.24
Flabitz,Bubba,1712.38
Blackwell,Sharon,1872.93
Molerat,Rufus,501.00
Goodall,Jane,1567.43
Sommerset,William,1359.57
[Code] ......
I am trying to take a Text File mydata.txt and import it into a structure however when I try to run this code it just closes out.
Code:
#include<stdio.h>#include<stdlib.h>
#include<string.h>
#include<ctype.h>
struct hard_disk{
char name[18];
double size;
[Code] .....
I am doing a project in C++ - a simple data base (with "one table"). I want to build that data base using a LIFO or FIFO list, but this doesn't matter here
The only problem I have is that the structure of the data base is not "locked" in the code of the program, but when the program starts, it is "loaded / implemented" from a "configuration file" called "data.txt".
So the user, before she or he runs my program opens the file "data.txt" and writes the structure of the data base that se/he wants to create. This means that one time my program can be used to create a data base of students with fields such as "name / surname / gender / age / idnumber / university" but the next time it can be used for a data base of CD's with fields like - "author / release date / no. of tracks / etc.".
How to do that "loading" of a structure of a data base from a file, when the user runs my data-base creator (my C++ program).
I am doing a project in C++ - a simple data base (with "one table").
I want to build that data base using a LIFO or FIFO list, but this doesn't matter here . The only problem I have is that the structure of the data base is not "locked" in the code of the program, but when the program starts, it is "loaded / implemented" from a "configuration file" called "data.txt".
So the user, before she or he runs my program opens the file "data.txt" and writes the structure of the data base that se/he wants to create. This means that one time my program can be used to create a data base of students with fields such as "name / surname / gender / age / idnumber / university" but the next time it can be used for a data base of CD's with fields like - "author / release date / no. of tracks / etc.".
How to do that "loading" of a structure of a data base from a file, when the user runs my data-base creator (my C++ program).
For some reason, my input seems to lag one behind when inserting data. Attached, I have code that I wrote along with the example of the lag. What may be wrong with my code that is causing this to lag?
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