class knygos {
public:
int nr;
char pavadinimas[25];
char autorius[25];
int egz_sk;
void go_to(int x, int y) {
COORD c;
c.X = x - 1;
c.Y = y - 1;
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), c);
}
void knygu_sarasas() {
ifstream myFile("data.bin", ios::in | ios::binary);
while (myFile.read ((char *) this, sizeof (knygos))) {
go_to(2,6);
cout << nr << endl;
cout << "Pavadinimas" << pavadinimas << endl;
cout << "Autorius" << autorius << endl;
cout << "Egzemploriai "<< egz_sk << endl;
}
myFile.close();
}
};
void main() {
knygos ob;
ob.knygu_sarasas();
}
Why when I use function go_to(2,6); while loop work only 1 time, when i not use this function loop work normaly (6 times) I not know where is problem, plese help guys ;)
Do you realize that if you set the cursor IN the loop to the (2, 6) position, all interation will wite to the SAME place, effetivly overwriting each other, and only producing "one" output for all 6 or many cicles?
You can using ncurses library for type of input such as keyboard/mouse and and output such as screen.If you use mvprintw() family functions,You can set X and Y same as gotoxy in DOS.
I forgot cout and cin and use ncurses library, you can learn it from here.
Related
int strtnumber,endnumber,remainder,i;
gotoxy(2, 0);
printf("Enter Start value: "); //enters start number
cin >> strtnumber;
gotoxy(2, 1);
printf("Enter End Value: "); //enters end number
cin >> endnumber;
cout << "==================================================="<< endl;
for (; strtnumber <= endnumber; strtnumber++) {
remainder = strtnumber % 2;
if (remainder == 1) {
cout << strtnumber << endl;
}
if (remainder == 0) {
cout << strtnumber << endl;
}
}
I would like to separate the odd and even numbers using gotoxy
This is the output I would like to achieve:
ODD | EVEN
1 | 2
3 | 4
5 | 6
I would like to separate the odd and even numbers using gotoxy This is
the output I would like to achieve:
Almost every system with which I have worked has ansi terminal's available. Even the embedded systems would be connected (via RS232) to VT100's or equivalent.
PC's come equipped with ansi term emulators, or the emulators can be trivially downloaded and installed.
Note: The comments provided are clear, Ansi i/o is not part of C++.
But you can easily find example code to invoke the ansi terminal functions you might want.
Here is a useful part of my own class which has worked on every version of Ubuntu Linux, and multiple Linux terminal emulators, and vxWorks, etc. I currently use an emulator installed with Lubuntu. Have not found the name, but the help references Qt_io:
#include <iostream>
using std::cout, std::endl;
#include <string>
using std::string, std::to_string;
class Ansi_t // provide access to features of ansi-compatible terminal
{
public:
string clrscr (void)
{ return '\033' + string("[H") + '\033' + string("[2J"); }
// --v------v- C++ 2d array indexing is 0 based
string gotoRC(int r, int c) {
return ('\033' + string("[") +
to_string(r+1) + ';' + to_string(c+1) + 'H');
} // 0 ^ 0 ^
// 1,1 is top left of ansi screen
// tbr - add other ansi functions here
}; // class Ansi_t
// usage: declare an instance, Ansi_t ansi;
// invoke method: std::cout << ansi.clrscr() << std::endl;
// invoke method: std::cout << ansi.gotoRC() << std::endl;
// to specify a named escape sequence ^^^^^^^^
// Ubuntu gnome-terminal ansi term cursor locations are
// 1-based with origin 1,1 at top left corner
class Hello_t // demo executable
{
Ansi_t ansi; // declare an instance
public:
Hello_t() { cout << ansi.clrscr() << ansi.gotoRC(9, 18) << "Hello "; }
~Hello_t() { cout << " world!\n\n\n" << endl; }
int operator()() { cout << "C++"; return 0; } // functor entrance
};
int main(int , char* * ) { return (Hello_t()()); }
I recently tried making a program that has several functions outside of main, but for some reason the "declaration is incompatible with" all of my variables and functions. Is there an easy way of using functions outside of main and refer to the variables interchangably? The error i receive is:E0147. and this is my code:
#include <iostream>
using namespace std;
int dager;
int mintemp;
int maxtemp;
int nedbor;
int i = 1;
int j;
int mintempg;
int maxtempg;
int nedborg;
int mintemp() {
cout << "hva er dag:" << i << " sin min temp? \n";
cin >> mintempg;
if (mintempg >= -70 && mintempg <= 70)
{
mintemp += mintempg;
}
else
{
cout << "ugyldig temperatur.";
mintemp();
}
}
int maxtemp() {
cout << "hva er dag:" << i << " sin max temp? \n";
cin >> maxtempg;
if (maxtempg >= mintempg && maxtemp <= 70)
{
maxtemp += maxtempg;
}
else
{
cout << "ugyldig temperatur.";
maxtemp();
}
}
int nedbor() {
cout << "hva er dag:" << i << " sin mm nedbør? \n";
cin >> nedborg;
if (nedborg >= 0 && nedborg <= 200)
{
nedbor += nedborg;
}
else
{
cout << "ugyldig mengde nedbor.";
nedbor();
}
}
int main() {
cout << "Hvor mange dager er det i måneden? " << "\n";
cin >> dager;
for (j = dager; j > 0; j--) {
if (dager >= 28 && dager <= 31)
{
mintemp();
maxtemp();
nedbor();
i++;
}
}
system("pause");
}
So as you can see it provides a lot of readability to my code to do it like this, which is why i decided i didn't want all of it to be in main. Also it makes it easier to reuse the code later.
Side question: Is there a way I can make the compilator not close whenever it has run through code without using system("pause"); ?, I seem to recall our professor mentioning it in one of our lectures, but I didn't quite catch it. Anyways all help appreciated !!
For your side question; In order to prevent the window from closing look at this post.
-If you are using Visual Studio and you are starting the console application out of the IDE: pressing CTRL-F5 (start without debugging) will start the application and keep the console window open until you press any key.
-You could insert std::getchar(); at the end of your main function. The function is included by .
reference: stackoverflow.com/questions/2529617/...
I'm having a little trouble with my code. It's pretty much supposed to open two files, and compare the first twenty line of the file "StudentAnswers.txt" [inputted as a char into a char array] against a char value in (each line of another file) "CorrectAnswers.txt" in another array at the same position (index). It's like a linear search, but the same position in the arrays. Then a report should be displayed, detailing which question the student missed, the given answer, the correct answer, and if the student passed (got >= 70%) or not, like the following:
Report for Student X:
2 (A/D), 3 (C/D), 5(D/A)
This student passed the exam!
Then it should clear the SAArray, and feed the next twenty lines from StudentAnswers.txt, and start the process all over again. I guess the program has to determine the number of students from (lines of 'StudentAnswers.txt' file / 20).
I'm having trouble displaying the report, and having the array clear itself after the program. I'm guessing this can be done with a while loop and an accumulator for the number of students (to be determined by above equation).
Also, Visual Studio seems to go to "Missed __ questions for a total of ___ %", and then keep looping -858993460.
Any help would be appreciated.
#include <iostream>
#include <fstream>
#include <string>
#include <array>
#include <algorithm>
using namespace std;
void GradeReturn(char[], char[], int, int, int);
string PassFail(float);
int main()
{
ifstream SA("StudentAnswers.txt");
ifstream CA("CorrectAnswers.txt");char CAArray[20];
char SAArray[20];
// char SA2Array[20];
bool isCorrect;
int correct;
int incorrect;
int counter;
correct = 0;incorrect = 0;
counter = 0;
cout << endl;
if (!SA.fail())
{
cout << "'StudentAnswers.txt' file opened successfully." << endl;
cout << "'CorrectAnswers.txt' file opened successfully." << endl << endl;
int a = 0;
int b = 0;
while (a < 20)
{
CA >> CAArray[a];
a++;
} // while loop to feed char into the array
while (b < 20)
{
SA >> SAArray[b];
b++;
}
} // while loop to feed char into array
CA.close(); // closing "CorrectAnswers.txt"
SA.close(); // closing "StudentAnswers.txt"
GradeReturn(&CAArray[counter], &SAArray[counter], correct, incorrect, counter);
return 0;
}
void GradeReturn(char CAArray[], char SAArray[], int correct, int incorrect, int counter)
{
float percent;
float hundred;
int student;
int catcher[20];
int writeCatcher; int starter;
int catcher_size;
student = 0;
writeCatcher = 0;
catcher_size = ((sizeof catcher) / 4);
while (counter < 20)
{
if ((CAArray[counter]) == (SAArray[counter]))
{
correct++;
cout << "Good job!" << endl;
} // correct handling
else
{
incorrect++;
cout << "You got question " << counter << " wrong." << endl;
counter >> catcher[writeCatcher];
writeCatcher++;
} // incorrect handling
counter++;
} // while loop to determine if a student got a question right or wrong
static_cast <float> (incorrect); // float conversion
cout << endl; // for cleanliness
percent = ((static_cast <float> (correct)) / 20); // percentage
hundred = percent * 100;
PassFail(percent);
if (PassFail(percent) == "pass")
{
student++;
cout << "Report for Student " << student << ":" << endl;
cout << "-----------------------------" << endl;
cout << "Missed " << incorrect << " questions out of 20 for ";
cout << hundred << " % correct." << endl << endl;
starter = 0;
while (starter < (sizeof catcher)
{
if(1=1)
{
catcher_size
}
else
{
cout << "";
starter++;
}
}
}
else if (PassFail(percent) == "fail")
{
student++;
cout << "Missed " << incorrect << " questions out of 20 for ";
cout << hundred << " % correct." << endl << endl;
while (starter < catcher_size)
{
if ((catcher[starter]) == -858993460)
{
starter++;
}
else
{
cout << "";
starter++;
}
}
}
return;
}
string PassFail(float percent)
{
if (percent >= 0.70) // if <pass>
{
return "pass";
}
else // if <fail>
{
return "fail";
}
cout << endl;
}
To get a loop you should keep streams open instead of closing them after reading 20 lines.
As pseudo code that would be:
a = 0;
while(streams_not_empty)
{
CA >> CAArray[a];
SA >> SAArray[a];
++a;
if (a == 20)
{
GradeReturn(&CAArray[counter], &SAArray[counter], correct, incorrect, counter);
a = 0; // Reset a
}
}
CA.close(); // closing "CorrectAnswers.txt"
SA.close(); // closing "StudentAnswers.txt"
You would also need to pass correct, incorrect, counter by reference so that the GradeReturn can change their value and their by do the accumulation.
Like:
void GradeReturn(char CAArray[], char SAArray[], int& correct, int& incorrect, int& counter)
Further you shouldn't rely on being able to read exactly Nx20 lines from the files every time. A file could have, e.g. 108 (5x20 + 8) lines, so you code should be able to handle the with only 8 lines. In other words, don't hard code 20 in your function like while (counter < 20). Instead pass the number of lines to be handled and do while (counter < number_to_handle).
Something like this as pseudo code:
a = 0;
while(streams_not_empty)
{
CA >> CAArray[a];
SA >> SAArray[a];
++a;
if (a == 20)
{
GradeReturn(&CAArray[counter], &SAArray[counter], correct, incorrect, counter, a);
// ^
a = 0; // Reset a
}
}
if (a != 0)
{
// Process the rest
GradeReturn(&CAArray[counter], &SAArray[counter], correct, incorrect, counter, a);
}
CA.close(); // closing "CorrectAnswers.txt"
SA.close(); // closing "StudentAnswers.txt"
One problem you have is you're trying to compare C-style strings with the == operator. This will compare them essentially as if they were pointers to char, i.e. compare whether they point at the same location in memory, not compare the contents of the string. I urge you to look up array-decay and c-string variables to understand more.
Specifically, if (PassFail(percent) == "pass") isn't going to do what you want it to. strcomp doc, strncmp doc using std::string variables instead of c-style strings would all work, but it would be better simply to compare percent to a value, i.e. if(percent >= 0.70 directly instead of calling PassFail and comparing a string.
There are many other issues here also, you at one point call PassFail but do nothing with the return value. The only side affect of PassFail is cout << endl, if that's what you intend, it's a poor decision and hard to read way to put a newline on the console.
Try asking your compiler for more warnings, that's often helpful in finding these types of issues. -Wall -Wextra work for gcc, you may have to read your compiler manual...
i have a problem with one assignment that i have. I have to read a .ts file, read the packets that are inside and extract header information from each packet.
I have created a struct Packet that will hold all the info of the header, and i also have a vector in which i will push_back each Packet.
The problem is that the for loop stops for some reason on the 163rd loop. If i loop until lets say i=160, then the code escapes ends the loop, but when i print the vector.size() i get a really huge number which doesn't make sense. i guess it should be an integer value as high as the pushed back number of Packets.Here is the code that i have so far:
int main() {
FILE *ts_file = NULL;
ts_file = fopen64("/home/ddd/Desktop/Assignment/Streams/ddd.ts", "rb");
if (ts_file == NULL){
cout << "No file detected on this path, try again" << endl; // prints !!!Hello World!!!
}
TS_Analyzer *ts_analyzer;
ts_analyzer->parse_file(ts_file);
cout << "Finished main" << endl;
return 0;
}
void TS_Analyzer::parse_file(FILE *ts_file){
cout << "Inside parser" << endl;
fseek(ts_file,0,SEEK_END);
long file_size = ftell(ts_file);
rewind (ts_file);
number_of_packets = file_size/PACKET_SIZE;
unsigned int current_header_add = 0;
unsigned int i=0;
for (unsigned int j=1; i<number_of_packets; j++)
{
i++;
unsigned char TS_raw_header[4];
cout << "current position " << int(current_header_add) << endl;
current_header_add = ftell(ts_file);
fread(&TS_raw_header, sizeof(TS_raw_header), 1, ts_file);
Packet current_packet;
current_packet.sync_byte = TS_raw_header[0];
current_packet.transport_error_indicator = (TS_raw_header[1] & 0x80) >> 7;
current_packet.payload_start_indicator = (TS_raw_header[1] & 0x40) >> 6;
current_packet.transport_priority = (TS_raw_header[1] & 0x20) >> 5;
current_packet.PID = ((TS_raw_header[1] & 31) << 8) | TS_raw_header[2];
current_packet.transport_scrambling_control = (TS_raw_header[3] & 0xC0);
current_packet.adaption_field_control = (TS_raw_header[3] & 0x30) >> 4;
current_packet.continuity_counter = (TS_raw_header[3] & 0xF);
stream_packets.push_back(current_packet);
//cout << hex << int(current_packet.PID) << endl;
//cout << dec << "continuity counter " << int(current_packet.continuity_counter) << endl;
cout << " i " << int(i) << endl;
fseek(ts_file, 184, SEEK_CUR);
}
cout << "##" << endl;
cout << stream_packets.size() << endl;
}
class TS_Analyzer: public Analyzer {
public:
TS_Analyzer();
~TS_Analyzer();
struct Packet {
unsigned char sync_byte;
unsigned char transport_error_indicator;
unsigned char payload_start_indicator;
unsigned char transport_priority;
unsigned int PID;
unsigned char transport_scrambling_control;
unsigned char adaption_field_control;
unsigned char continuity_counter;
};
std::vector<Packet>stream_packets;
int number_of_packets = 0;
void parse_file(FILE *);
};
Any ideas of why the vector push_back breaks the for loop and why i cannot get a correct vector size?
If I put this code through the clang compiler, I get an error on following code:
TS_Analyzer *ts_analyzer;
ts_analyzer->parse_file(ts_file);
>> variable 'ts_analyzer' is uninitialized when used here
I guess you are encountering undefined behavior: As ts_analyzer as ptr is any random value, the data in its members is also very random.
I'm actually surprised that this code runs at all without crashing, though you can always be lucky.
If you like to fix this, try avoiding pointers by creating the object at the stack:
TS_Analyzer ts_analyzer;
ts_analyzer.parse_file(ts_file);
or if you really need allocated memory, at least fill in the pointer:
auto ts_analyzer = std::make_unique<TS_Analyzer>();
ts_analyzer->parse_file(ts_file);
I've been pulling my hair out trying to figure out this program. The class has to hold 3 player's info and output their info. My output function is not outputting from my set/get functions. Also, if I output the array indexes the program crashes (that's the array indexes are commented out in the Output function).
edit: I'll just show one profile to keep the code smaller
Any help is appreciated.
#include <cstdlib>
#include <iostream>
using namespace std;
class PlayerProfile
{
public:
void output();
void setName1(string newName1); //player's name
void setPass1(string newPass1); //player's password
void setExp1(int newExp1); //player's experience
void setInv1(string newInv1[]); //player's inventory
void setPos1(int newX1, int newY1); //player's position
string getName1();
string getPass1();
int getExp1();
string getInv1();
int getPos1();
private:
string name1;
string pass1;
int exp1;
string inv1[];
int x1;
int y1;
};
int main(int argc, char *argv[])
{
PlayerProfile player;
cout << "This program generates three player objects and displays them." << endl;
cout << endl;
player.output();
system("PAUSE");
return EXIT_SUCCESS;
}
void PlayerProfile::setName1(string newName1)
{
newName1 = "Nematocyst";
name1 = newName1;
}
void PlayerProfile::setPass1(string newPass1)
{
newPass1 = "obfuscator";
pass1 = newPass1;
}
void PlayerProfile::setExp1(int newExp1)
{
newExp1 = 1098;
exp1 = newExp1;
}
void PlayerProfile::setInv1(string newInv1[])
{
newInv1[0] = "sword";
newInv1[1] = "shield";
newInv1[2] = "food";
newInv1[3] = "potion";
inv1[0] = newInv1[0];
inv1[1] = newInv1[1];
inv1[2] = newInv1[2];
inv1[3] = newInv1[3];
}
void PlayerProfile::setPos1(int newX1, int newY1)
{
newX1 = 55689;
x1 = newX1;
newY1 = 76453;
y1 = newY1;
}
string PlayerProfile::getName1()
{
return name1;
}
string PlayerProfile::getPass1()
{
return pass1;
}
int PlayerProfile::getExp1()
{
return exp1;
}
string PlayerProfile::getInv1()
{
return inv1[0], inv1[1], inv1[2], inv1[3];
}
int PlayerProfile::getPos1()
{
return x1, y1;
}
void PlayerProfile::output()
{
cout << "Player Info - " << endl;
cout << "Name: " << name1 << endl;
cout << "Password: " << pass1 << endl;
cout << "Experience: " << exp1 << endl;
cout << "Position: " << x1 << ", " << y1 << endl;
cout << "Inventory: " << endl;
/*cout << inv1[0] << endl;
cout << inv1[1] << endl;
cout << inv1[2] << endl;
cout << inv1[3] << endl; */
}
This is the output that I am getting:
This program generates three player objects and displays them.
Player Info -
Name:
Password:
Experience: -2
Position: 3353072, 1970319841
Inventory:
Press any key to continue . . .
I'm sorry if I sound like an idiot, this is the first time I have programmed with classes and I am very confused.
First:
You do not have a constructor declared or defined in your class so when you compile, the compiler provides you with a default constructor.
The line
PlayerProfile player;
calls the default constructor provided by the compiler. This default constructor only allocates memory for your class member variables, but does not set their values. This is why name1, pass1, exp1, x1, y1 are not outputting what you expect.
Second:
C++ will not call get or set functions for you, and I think you are misunderstanding how c++ functions work.
this
void PlayerProfile::setName1(string newName1)
{
name1 = newName1;
}
is a function definition. You do not need to assign newName1 inside the function. It's value is passed to the function when a line like
setName1("Nematocyst");
is executed.
If you write a constructor, you can use it to call your set functions, and pass them the values you want to set member variables to.
If you do not want to write a constructor, you can call class functions/methods from main with:
player.setName1("Nematocyst");
Third:
Your program crashes because you are not using arrays properly. Here is a tutorial on how to declare an array and access it's contents.
Generally, I think you are trying to run before you know how to walk. Try not to get frustrated. Learn how arrays work, how functions work, and then how classes work. I hope this is not your homework assignment!