so i have to read a text file with an unknown number of lines and allocate memory to for the number of items in the text file.currently i read the entire file(counting the number of lines). i allocate memory according to the number of lines read and then use fseek() with an offset of zero to allow for the second read .
View 5 RepliesWhen you have to write data on a file in binary mode multiple times (without closing the file), is the put pointer left where you ended writing the last time, or do you have to use tellp() or seekp() again and again to make sure you write at the right place?
I would have the same question about the get pointer, does he stay in place after you're done reading something (without closing the file, of course), or do you have to set it back at the right place with seekg() ??
I have a question about SDL and drawing sprites (SDL surfaces). My idea is that the user can create a wall of separate sprites by create one sprite each time in the current mouseX and mouseY position, when the user push down the e-key. The problem is that I have no idea how I could draw the same sprite multiple times without to delete the previous one.
View 3 Replies View RelatedI've been stuck on this for hours, and have scoured the internet for any insight on this particular issue with no luck.
I'll simplify the problem here. I have a lines in an input file:
John Smith 1234 Main St New York
Carol Thomas 5678 5th Ave Columbus
...
and I am reading into character arrays using code like this:
infile.getline(name,20);
infile.getline(street,15);
infile.getline(city,10);
but when I print the output using something like this:
outfile << "Owner Name: " << name << endl;
outfile << "Address: " << street << city << endl;
(let's pretend I included spaces between the address components, which I omitted to save space)
I get an output file of:
Owner Name: John Smith
Address:
The output stops after the name variable, which I believe is stored correctly. I don't think anything is storing in the address pieces, this is the problem.
I think it's because I'm not using getline() properly in this case. Can you string together multiple getline()s like that?
If this was my design, I'd read in strings instead, but that is not possible in this case.
I've been working on a program that uses a reference counting class that I've written which works fine for objects that inherit from it however I now need to have the following setup:
class SBComponent : private Refcounted { /*stuff*/}
class ProxiedComponent : public SBComponent, private Refcounted {/*stuff*/}
The compiler gives the following warnings
warning: direct base ‘Refcounted’ inaccessible in ‘ProxiedComponent’ due to ambiguity
And then several repeats of the error:
error: request for member ‘bk’ is ambiguous
Back *b = bk<ProxiedComponent>();
bk is a templated function that's defined in Refcounted and returns a pointer of type <template arg>::Back (ProxiedComponent::Back in this case).
I don't understand why the call to bk is ambiguous as although there's two instances of Refcounted (there needs to be with the way I've designed it so I can't make it virtual) it's inheritance is private in both cases so there should only be one instance of it visible in ProxiedComponent.
I've been struggling with an object when trying to add it to a list with [Listname].push_back. You see, I have a list with some objects that will be rendered in the screen (Called objects) and a function to create a text box with some text. The function in question is the following:
void reprEv(int evNum, ALLEGRO_BITMAP *txtbxim) //Event to call, default text box image.
{
textBox *txtBox = new textBox("Line 1 ", "Line 2 ", "Line 3 ", "Line 4 ", "Line 5 ", textboximage);
objects.push_back(txtBox);
[Code]....
(txtNum is increased then space is pressed, and when certain screen (maxScreen) have been shown, then it will go to the playing state)
My problem begins when the text box is created, because it's supposed to add only 1 text box to objects list, but instead adds hundreds of text boxes to objects.
I'm currently working on a server for handling clients in a 2d online game and I wrote some regular fstream file code for handling the file that stores their information and I was about to implement it into the server, then I realized there might be a problem having it open multiple times concurrently, so I googled it and came up with
posts like
[URL]
I'm wondering if I can just treat it like everything else or will I have to do something specific for opening on multiple threads?
p.s. I did read those posts but I'm very new to multithreading
My application calls malloc in multiple subroutines, finally releasing all using free. This is done using my zalloc library (see my other post: [URL] .....
Somehow, when the applications tries to detect the available ammount of memory at the end of the test (allocating, freeing, testing), the freemem function gives me about 4-6MB less memory than at the start of the test? (out of 21MB available on the device at the start).
All memory is allocated and freed using the malloc/free routines within the library, with the exception of the SDL functions, which are registered externally on allocation and release.
So I have this text file that I am trying to read from and store the values of each line in multiple variables.
Let's say my text file contains
AXSYZ3482 Tom 100 112
and my code below here works fine when the lines in the text file is separated by spaces.
while (fscanf(fp, "%s %s %d %d
", userID, name, &startLoc, &endLoc) != EOF) {
printf("%s %s %d %d
", userID, name, startLoc, endLoc);
}
But let's say my file was to look like this instead.
AXSYZ3482:Tom:100:112
But if i try this below...
while (fscanf(fp, "%s:%s:%d:%d
", userID, name, &startLoc, &endLoc) != EOF) {
printf("%s %s %d %d
", userID, name, startLoc, endLoc);
}
It seem to store the entire line in userID including the ":". I want to ignore the ":"'s and store everything in between in respective varibles in the order specified above.
So first string in userID, then ignore the :, then second string in name, and ignore the next :, and so forth. How I can accomplish this?
I am beginner at C and I was working on a program where I have to read in a line such as Digit, String, Float. The string can have any amount of spaces between it. and each input is separated by a space character.
The input is of the format:
10000000000 hello my n ame is 30.2
So I used fgets(x,100,stdin) to read the line in.
So I need to read that line into an int, array, and float.. so I was thinking of using this:
sscanf(x, "%d %[^/n] %f", &number, &username, &numberfloat);
Now, obviously I can't use the /n to read in the username with spaces because I need to read the 30.2 into a float variable.
<?xml version="1.0" encoding="ISO-8859-1" ?>
<packets_summary>
<item>
<index>1</index>
<frame_type>Ethernet</frame_type>
<local_mac_address>00-21-85-11-29-1b</local_mac_address>
[Code] ....
I am having trouble to read all attributes in all nodes called "item". I can load all attributes in one node "item" but I can't move to another node called "item " and load another attributes . I was trying a lot of different codes but I did not succsed.
for (pugi::xml_node node = doc.child("packets_summary").child("item").first_child(); node; node = node.next_sibling()) { cout << node.name() << ": " << node.child_value() << endl; }
This code just print all of the attributes in node called "item" but i need to move to another one and I really don't know how. I was trying to put into one for cycle another one but it did not work.
for (pugi::xml_node node = doc.child("packets_summary").child("item").first_child(); node; node = node.next_sibling()) { cout << node.name() << ": " << node.child_value() << endl; }
for (pugi::xml_node node = doc.child("packets_summary").child("item").first_child(); node; node = node.next_sibling()) {
cout << node.name() << ": " << node.child_value() << endl;
}
I wanted to know if there was a way to separate the inputs received if there were a few keyboards and mice hooked up to a desktop/laptop.
Would there be a particular class that would best be utilized to do this?
I read that MouseEventArgs is one class that can recognize events, but I'm not sure if its best for what I need.
I want to know how to read multiple text files in this program... I have 5 text files(order1,order2,...order5).
#include<iostream.h>
#include<fstream.h>
#include<conio.h>
#include<windows.h>
using namespace std;
class{
[Code] ....
My problem is to count the characters in a file and define how many times each one occurs.Characters who are not found must not be included in the table; The output must be a table - like that -
”| character | ASCII- DEC | ASCI – HEX | how many times it occurs |”
This my function:
Code:
int f2(FILE *p1)
{
FILE *g3;
int char_count[256]={0};
char ch;
int n=0;
if(!(g3=fopen("D:zz.txt", "w"))){
[Code] ....
It must look like this:
| D | 68 | 44 | 2 |
| 2 | 50 | 32 | 1 | and so on...
I'm trying to make program that will read text from a file and show what words occur how many times. I'm trying to make it so that if a new string comes, it saves it into wlist[], and counts 1 to wcount[]. If the same word is there, it will just add 1 to wcount[]. The program will end when it gets to the end of a file.
I don't know the reason, but I can't get strcmp and strcpy to work. I had to put a pointer in curword, just to make it compile.
Code:
#include <stdio.h>
#include <string.h>
#define LIST_MAX 100
#define WORD_MAX 20
int main(){
[Code] ....
I am writing this program that is supposed to read a file, put the data into an array, alphabetize, count how many times each word appears and print to an output function. I posted before on how my program had an error when I ran it but I have fixed that. Now my outputArray file is empty. It gets created but there's nothing in it.
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
using namespace std;
//global to this file
[Code] .....
I want to read a string of unknown length from stdin. I tried to follow the approach from this link.
[URL]....
My code is like this:
Code:
#include <iostream>
#include <string>
using namespace std;
int n;
cin >> n;
cout << "The value of n is " << n << endl;
string str;
getline(cin, str);
cout << "The entereed string is " << str << endl;
What I have noticed is that if I take integer input from cin (cin >> n in the above code before getline, the control does not stop on getline to take str as input from the console. If I don't do (cin >> n) before getline then the control stops on getline and takes the string as input.
What is the best way to read from console multiple strings of unknown length in combination with the integers?
I have written a C++ program I have multiple of CSV file used as input, which I open one at a time and close it after extracting data to a output file which is the only file.
I run getline(inFile,line);
outFile << line << endl;
I run this code, and only part of it is goes to the output file I got, also have spacing randomly to specific file and inconsistent
But when I slower the code, like system("Pause") in the loop, I can get extract what I want perfectly....
Is my program running to fast, why getline would be skipping part of what things I want?
Program background: Ticket Sales Details You will sell tickets in advance and at the door. Prices for buying in advance and at the door will be given. Also, the total number of tickets sold in advance will be given. Each guest will have a unique number. If there are n tickets sold in advance, then these guests will be numbered 0 through n-1. As the event starts, requests to buy tickets at the door may be made and these guests will be numbered sequentially, starting at the lowest unassigned number. The maximum number of guests will be 1000. The first line of the file contains the following three values, separated by spaces: Cost of the presales tickets (in dollars), Cost of the tickets at the door (in dollars), and the number of presale tickets. The first two values will be positive real numbers to two decimal places and the last will be a positive integer.
The second line of the file will contain one positive integer representing the number of auction items followed by a positive real value to two decimal places (at most) representing the minimum bid increment, in dollars. The first value is guaranteed to be 1000 or less and the second will be in between 1 and 50, inclusive.
The third line of the file will contain all the prices of the auction items, in dollars, separated by spaces, in order. Thus, the first price is the price of item 0, the next price is the price of item 1, and so on. These values will be real numbers represented to up to 2 decimal places.
The fourth line of the file will contain the three following positive integers pertaining to the raffle: the number of raffle tickets available, the cost of a raffle ticket in dollars, and the number of raffle prizes. (It's strange to have raffle tickets that don't cost a whole number of dollars.)
The fifth line of the file will contain each of the values of the raffle items, in dollars, separated by spaces, in order. Thus, the first price is the price if item 0, the next price is the price of item 1, and so on. These values will be real numbers with upto 2 decimal places.
The sixth line of the file will contain ten positive integers representing the number of each of the drinks 0 through 9, in order, that are in stock.
The seventh line of the file will contain ten positive real numbers with upto 2 decimal places representing the price of each of the drinks 0 through 9, in order.
The eighth line of the file will contain a single positive integer, numEvents, representing the number of events that occur at the charity ball. These events are split into two groups: actions by guests at the ball and awards given (raffle, auction, person, totalrevenue). All of the actions precede all of the awards. You will produce exactly one line of output for each event described. Here are the formats of each event that could occur:
If a patron buys a ticket at the door, a command will be on a line by itself:
BUY TICKET k
where k is a positive integer indicating the number of tickets bought at the door. These guests will be numbered as previously mentioned. You are guaranteed that the total number of tickets bought, including presales, will not exceed 1000. This is what I have so far and I cannot figure out why it wont calculate the total revenue. I am not completely sure if it is even accessing the if statement in main.
Code:
#include <stdio.h> #include <stdlib.h>
#include <string.h>
#define N 1000
[Code].....
I am attempting to break up a file into smaller chunks and have it process the different parts of the file in parallel to speed up the entire process. I was thinking maybe 4 chunks at a time. How do I get my program to do this? Is there a good book explaining parallel processing in C?
View 7 Replies View RelatedI am trying to read text from a file that includes
lastname firstname bloodpressure
for example:
Jones Tom 110/73
determine whether the blood pressure is normal, above normal, or below normal and then create a line that reads...
lastname, firstname has normal blood pressure bloodpressure
For example: Jones, Tom has normal blood pressure 110/73
All I can get is the entire line. I cannot find the correct code to get word for word or int. My code is this...
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using namespace std;
int main() {
string x;
[Code] ....
I need making a function that is deciphering multiple strings from a .txt file. The function is supposed to remove all instances of the first three characters from the string.
An example would be from l.pjkjsdfl.p[)sdfslkl.p ------> jkjsdf[)sdfslk
Basically it removes "l.p" from wherever it is in the string.
I am new to C++ and I don't know where to start from.
So say I create a header file which contains a list of structs, and I want to use these structs through out my source and some of my classes... how would I accomplish this?
When I try to do it via #include, I get re-definition errors, due to the nature of #pragma once. If I switch to #ifndef then I lack defenitions in files other than the source.
Is there a way to define things such as structs across multiple files, which doesn't lead to re-definition errors, and doesn't involve manually re-created all the structs for each file?
I'll start with my code.
#ifndef H_cylinderType
#define H_cylinderType
class cylinderType {
public:
void getRadius(double radius);
void getHeight(double height);
[Code] .....
I have read the section in the book but I am still unsure on how to use 2 header files. In my cylinderType header file, am I wanting to include
#ifndef H_cylinderType
#define H_cylinderType
public:
void getRadius(double radius);
void getHeight(double height);
[Code] .....
I'm trying to load a file that look like this:
IP:123.123.123.123
Port:12345
I can't figure out how to load multiple lines. I tried using , but I can't get it to work. Is there a better way of doing it than I am right now? This is my code.
char message[100];
int messageCount = 0;
for(unsigned int i = 0; i < file.size(); ++i) {
message[i] = file[i];
[Code] ....
I am reading a file then printing the data onto the other file. It is working, however when I check to see if each variable is being properly set after reading the file a issue arises.
Example of the file being read
Code:
Vehicle PV50CAN passed camera 1 at 05:33:26.
Vehicle W867BRO passed camera 1 at 05:33:29.
Vehicle KQ63ARU passed camera 1 at 05:33:38.
Vehicle K954ITQ passed camera 1 at 05:33:40.
Vehicle V220MXB passed camera 1 at 05:33:42.
[Code] .....