I have an array of structures with structure def that looks like.
Code:
struct {
char * name;
char * school;
int age;
}
there are multiple people with same name but different ages so i want to list them like.
Name.
age 1
age 2 and so on
The array is sorted by name already.
I'm trying to sort my vector, find duplicate values using unique and erase them. Program can compile successfully but the duplicates are not removed.
output:
x: 3
y: 2
x: 6
y: 4
x: 3
y: 2
vector<Point2D> p2dvector;
void readData()
[Code].....
I also have operator== in my Point2D class which I understand it is required to use unique for vector.
bool operator==(const Point2D& lhs, const Point2D& rhs)
{
return lhs.x == rhs.y;
}
I have a text file that needs to be read by command line arguments. The text are all numbers and can have multiple numbers on one line separated by a space. I cannot use an array or sort the numbers.So say I have a text file, listNums.txt:
12
473 8 29
30 1
8
248 17 55
29 84
5
Basically I need to read one number, find out if its odd or even by dividing by 2, search the odd or even doubly linked list that it would go into to see if its in there, if its not then add it to the bottom of the list.
I'm having some trouble printing the duplicates found in an array. Specifically, when the value is at more than 2 positions. So if the value 3 is at position 1, 10, and 11 it'll print three messages instead of two:
value 3 at position 1 is also at position 10
value 3 at position 1 is also at position 11
value 3 at position 10 is also at position 11
instead of
value 3 at position 1 is also at position 10
value 3 at position 1 is also at position 11
This is real simple problem, but I can't seem to figure it out. I've been trying to implement another array to 'remember' the encountered position, but I haven't had any luck.
Code:
for(i = 0; i < num_count; i++){for (j = i + 1; j < num_count; j++) {if (num[i] == num[j]){printf("
value %d at position %d is also at position %d", num[i], i, j);}}}
I have same question as posted by holla and Iam not sure about merging the contents of 2 sorted arrays into another array without duplication of values.
View 9 Replies View RelatedI have a question. How to find the average value of all the elements in a deque?
View 2 Replies View Relatedim trying to read employee information from a file using structures but im having problems with getting the file to open and read in the information
Code:
Write a programt that inputs (at most 50) records from a sequential file
#include <stdio.h>
#include <stdlib.h>
struct employee // employee structure definition
}
[code]....
I have asked a related question before, and it was resolved successfully. In the past, when I wanted to use std::max_element in order to find the maximum element (or even sort by using std::sort) of a vector of structures according to one of the members of the structure, all I had to do was to insert a specially designed comparison function as the third argument of the function std::max::element. But the latter comparison function naturally accepts two arguments internally.
For instance, here is a test program that successfully finds the maximum according to just one member of the structure:
Code:
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
[Code] ....
And the output was this, as expected:
Maximum element S.a of vector<S> vec is at: 9
[I]max element of vec.a between slot 3 and slot 6 is: 6, and its index is: 6 vec[6].a = 6
[I]max element of vec.a between slot 4 and slot 7 is: 7, and its index is: 7 vec[7].a = 7
[I]max element of vec.a between slot 5 and slot 8 is: 8, and its index is: 8 vec[8].a = 8
[I]max element of vec.a between slot 6 and slot 9 is: 9, and its index is: 9 vec[9].a = 9
However, I now need to search and find an element of vector<myStruct> according to just one member of myStruct, instead of finding the maximum or sorting as before. This presents a problem because the function std::find does not accept such a comparison function as its third argument.
This was the description of the std::find function that I found: find - C++ Reference
Code:
template <class InputIterator, class T> InputIterator find (InputIterator first, InputIterator last, const T& val);
I could also find another function called std::find_if, but this only accepts a unary predicate like this: find_if - C++ Reference
Code:
template <class InputIterator, class UnaryPredicate> InputIterator find_if (InputIterator first, InputIterator last, UnaryPredicate pred);
And once again this is either inadequate of I don't see how to use it directly, because for the third argument I would like to insert a function that takes two arguments with a syntax like this:
Code:
int x=7;
std::vector<S>::iterator result;
result = std::find(vec.begin(), vec.end(), []( const (int x, const S & S_1) { return ( x == S_1.a ) ; } ) ;
Is there another std function that I can use to make search and find an element according to just one member of myStruct?
Or perhaps there is a clever way to pass two arguments to the unary predicate.
How do I store pointers to a struct in an array ? I am using sprintf to concatenate some values together and then output it to an array in its 1st argument. A portion of my code is shown below.
Code:
int count = 0;
struct addx {
int a;
[Code].....
So i have a program with the structure
Code:
char record[20];
typedef struct{
int id;
char title[20];
char subject[20];
char faculty [20];
int level;
char fname[25];
}report;
int recno,i;
report list[100];
I need to store the hundred records into a file. What are the functions and elements i should use/introduce.
How to initialize this array of structures in my code
struct CustomerAddress; {
string street;
string city;
string state;
int zip;
[Code] ....
I am going to be using a boolean variable to mark whether or not a specific field has had data entered into it. I figure the best way to do that is to initialize all the elements of the structures to 0. However, with strings and with the nested structure, I'm not sure how to do this.
I have to write a program that reads from a text file, which contains a list of stock hourly prices and the company names. Something like this:
78.52 82.56 75.10 71.97 Water Company
22.40 25.68 21.37 22.96 Mega Shipping Inc
There's suppose to one array of companies, where each company will be kept in a structure that contains: a pointer for the name, an array of the prices, and the average price for the day. The structures will be kept in an array of structures.
My question is, how do I read the data from the file and put the data from each line into the next structure in the array of structures? I read the numbers in fine. I just use:
Code: fscanf(fp, "%f", &companyAry[i].hourlyPrices[j]);
But my program crashes when I try to read the name.
Code: fscanf(fp, "%[^]", &companyAry[i].companyName);
I'm thinking it has something to do with the fact the companyName is a pointer.
My structure looks like this:
Code:
typedef struct {
char *companyName;
float hourlyPrices[NUM_PRICES];
float avgPrice;
}
COMPANY;
so im trying to read in the name of a vendor into an array of structures. and write the name into a file.
#include <iostream>
#include <cstring>
#include <cctype>
#include <fstream>
using namespace std;
struct booth
[code]....
Any example to delete an element in an array of structure?Is it same as deleting an element in an array.ie like this....???
// to delete an element in an array
#include<iostream.h>
#include<conio.h> // for clrscr() and getch()
void main() {
clrscr();
int a[50],n,t,index,i;
[Code] .....
I am making a basic music library that stores information rather than files. I need to read from a .txt file the artist's name, the album name, the song name, and the song length. What I am confused about is storing the information in an array of Artist structures.
struct Song{
string songName;
int songLength;
};
struct Album{
[Code] ...
How to read the information into an array of Artists. Also, how would I be able to figure out if the artist already exists in the array when adding a song and if the artist does, add the album under the existing artist.This is how I am reading in the info:
Artist newArtist;
Album newAlbum;
Song newSong;
ifstream inF("library.txt");
while(!inF.eof()) {
[Code] ....
Suppose I have the following structure
struct b
{
char fullname[100];
char title[100];
bopname
};
and i declare a pointer to the struct as follows
b* bp;
and at runtime,
bp = new b[5];
In the end, is the statement delete[ ] bp enough to release the dynamically allocated memory. Or do i need to separately delete bp[0],bp[1]...
Does delete[ ] bp indicate that the array[ ] pointed by bp has to be deleted?? [I am confused as to how this happens, since the pointer only points at the 1st struct address]
I somewhere read "You cannot initialize a structure like that at run time."
Example:
struct item_info {
char itemname[15];
int quantity;
float retail;
float wholesale;
[Code] ....
But if you want to assign values at run time then you have to do it manually like:
strcpy(item[0].itemname, "rice");
item[0].quantity = 10;
item[0].retail = 40;
item[0].wholesale = 30;
I tried in internet but am unable to know the differences. I want to know the difference between those two in terms of run time and compile time. Explanation required also for below one. Is this run time or compile time? How does we actually decide which is run time and which is compile time!
struct item_info {
char itemname[15];
int quantity;
float retail;
float wholesale;
//int quatityonorder;
[Code] ....
I'm reading the following file:
Osgood,Marcus 298542123 CHM FR mosgood@whatever.edu
Cronk,Melissa 873489021 BIO SR mcronk@whatever.edu
Pry,Seth 349908431 MTH SO spry@whatever.edu
Langlais,Susan 783323545 ME SR slanglais@whatever.edu
Davis,Nicole 987543345 PHY FR ndavis@whatever.edu
It's supposed to split it up into name, ID number, major, year, and email. The file reads it without any errors, and assigns name to the first part of the structure. However, ID gets assigned the ID, major, year, and email. Then Major gets assigned major, year, and email. Year gets assigned year and email, while email just gets assigned email. I don't know if it has something to do with the loop. For example, this is what I get what I print just the name and the ID.
Cronk,Melissa 873489021BIOSRmcronk@whatever.edu
Pry,Seth 349908431MTHSOspry@whatever.edu
Langlais,Susan 783323545ME
Davis,Nicole 987543345 PHYFRndavis@whatever.edu
Anyway. This is my function code for reading the array. I have it printing the ID number just to see if I can catch the errors earlier:
Code:
#include <stdio.h>
#include <string.h>
#include "functions.h"
void read_data(char filename[], studentinfo_t s[], int *size) {
FILE *infilep;
int countstudents = 0;
infilep = fopen("student_data", "r");
[Code].....
the name is reading correctly, but not anything else!
I have to allocate memory for an array of structures, and my structure looks as following:
Code:
typedef struct {
char *name;
Uint *start_pos;
Uint len;
}
example_struct;
And now I want to allocate memory, for a variable number (so an array) of example_struct, so I first do:
Code:
example struct *all_struct;
int total_num = 3;
//will be set somehow, but for the example I set it on 3 all_struct = malloc (sizeof(example_struct) * total_num);
And now, as far as I now, I will have to allocate for each field of the structure memory, in order to be able to use it later. But I have problem at this point, a problem of understanding:
- I just allocated memory for 3 structures, but don't I have to allocate then memory for each structure separately, or can I just now allocate the fields like this:
Code: all_struct[0].name = malloc.....
But if yes, why the hell this works...
I am doing an exercise which has to do with International country codes.The user must give a code and the programm will display the corresponding country.
Code:
#include <stdio.h>
#define COUNTRY_COUNT
((int) (sizeof(country_codes) / sizeof(country_codes[0])))
[code]....
Background: I'm writing a convolutional encoder (and decoder, eventually) for a microprocessor (PIC24), for which I'm using structs and pointers to move from state to state. So far as I'm aware, everything I'm using in the PIC involves nothing other than ANSI C.
I have a little experience with structures, having written a linked-list program for a class a couple years back, but nothing since and never used structure arrays. I have the feeling I'm missing something basic here, which is what's so frustrating. The most confusing error (and I suspect the root of most of them) is the 'state undeclared', which I just can't figure.
The errors I'm getting are:
encoder.c:11: warning: 'struct memstate' declared inside parameter list
encoder.c:11: warning: its scope is only this definition or declaration, which is probably not what you want
encoder.c: In function 'state_init':
encoder.c:22: error: two or more data types in declaration specifiers
encoder.c:25: error: 'state' undeclared (first use in this function)
encoder.c:25: error: (Each undeclared identifier is reported only once
[Code]....
Code:
Code: //Includes
#include <stdlib.h>
//------------------------------------------------------------------------------
//Creates state machine and passes back pointer to 00 state
void state_init(struct memstate* startpoint)
{
extern struct memstate
{
char output0; //output if next input is 0
[code]...
NB: I'm aware that at the moment, this code will do nothing except spin round that do-while loop. Once it's actually compiling I'll drop in some simple button-based test code so it'll check for the correct output.
I am at a loss with an assignment. I am supposed to read from a text file, with an input of something like this: alphaproleone,stroke,42 1 and Store it into an array of structures and then output it with each word/number starting on a new line. My current code prints out only the first part, and the "a" in alphaproleone is the actual number "21".
#include <iostream>
#include <string>
#include<fstream>
#include<iomanip>
using namespace std;
typedef struct drugtype {
string name, target;
int effectiveness, toxicity;
[Code]...
I have been dealing with this problem for quite some time, I've been assigned to develop a program that can store products' information within structures (the number of products is undefined). I thought I should use an array of structures, but I don't know how to declare it properly. This is what I thought would work:
struct product {
string name;
string in_stock;
float sale_cost;
int id; }
prod [n]; //n being the undefined number of products the user will register/delete/modify
I already saw an example of array of structures, but it uses a defined number.
I want to do this but do not know exactly how to do it:
Create an array of space ship objects and write a program that continually updates their positions until they all go off the screen. Assume that the size of the screen is 1024 pixels by 768 pixels.
I have begun to write a bit code but the problem is when you want to see the space ship moving step for step on the screen I do not know how to create the ship visible so you can see it is moving. Here's my code so far
Code:
#include <iostream>
using namespace std;
struct SpaceShips
{
int x_coordinate;
int y_coordinate;
[Code ......
Code:
#include<stdio.h>
#include<string.h>
typedef struct test
{
char a[5];
char b[10];
}t;
[Code] ....
In Unix (HP-UX) and Linux, the output of above program will be:
t.a=Helloworld!
Instead of the value of t.a ,i.e, "Hello" only.
Why such output? And what is the trick here to print the only value of t.a.
Why I do have this error message?
1>------ Build started: Project: TMA04, Configuration: Debug Win32 ------
1>TMA04.obj : error LNK2019: unresolved external symbol "double __cdecl getFees(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?getFees@@YANV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function _main
1>C:UsersEvgericDocumentsVisual Studio 2010ProjectsTMA04DebugTMA04.exe : fatal error LNK1120: 1 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
