How to make a pair programming..
like I have 1 2 3 4 5 6 7
First, I want to make a pair of 91,20
(1,3)
(1,4)
(1,5)
using i=1, i<9,i++
nurulshidanoni
-1
Posting Whiz in Training
Recommended Answers
Jump to PostWell since you want to do it in a for loop, you must realize that this is probably a job for pointers since you can't make a for loop generate names for your variables to hold the class. What I would do is this:
int main() { …
Jump to PostIf you do not understand what pointers are or how they work, it would not be fitting to describe every aspect of them in this thread.
I will however give you a good tutorial on pointers, and when you practice with their examples, you should have a decent grasp …
Jump to PostCan you post your source now please? (and edit out the big error list, it is mostly the same error over and over again and is just a big waste of space)
I will see what you have and try to help you out.
Jump to Post1.
Did you make sure you kept what you had in front of main? I remove that from the code i posted as it is the same as you had, only the things in main were what i changed.2.
students.size is referring to a data member of an …
All 16 Replies
nurulshidanoni
-1
Posting Whiz in Training
I want to do like this, but how to call from i=0, i<11; i++, and how o insert in this program.
#include <iostream.h>
template<class C>
class Pair
{
public:
Pair(C, C);
Pair(Pair&);
void Display();
private:
C first;
C second;
};
template<class C>
Pair<C>::Pair(C left, C right)
{
first = left;
second = right;
}
template<class C>
Pair<C>::Pair(Pair<C>& p)
{
first = p.first;
second = p.second;
}
template<class C>
void Pair<C>::Display()
{
cout<<"(" << first <<","<< second <<")"<<"\n";
}
int main()
{
Pair<int> pi(2,3);
pi.Display();
return 0;
}
Joatmon
0
Junior Poster in Training
Well since you want to do it in a for loop, you must realize that this is probably a job for pointers since you can't make a for loop generate names for your variables to hold the class. What I would do is this:
int main()
{
const int SIZE = 8;
Pair<int> * pairs[SIZE]; // Declare an array of pointers to Pair<int>
for (int i = 0; i < SIZE; i++)
pairs[i] = new Pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array
pairs[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function
return 0;
}
nurulshidanoni
-1
Posting Whiz in Training
I dont understand
Joatmon
0
Junior Poster in Training
If you do not understand what pointers are or how they work, it would not be fitting to describe every aspect of them in this thread.
I will however give you a good tutorial on pointers, and when you practice with their examples, you should have a decent grasp of them, then you may come back to the example I gave previously and it should seem more clear.
nurulshidanoni
-1
Posting Whiz in Training
I understand now, but a lot of error.
error C2065: 'pairs' : undeclared identifier
error C2109: subscript requires array or pointer type
error C2061: syntax error : identifier 'Pair'
error C2109: subscript requires array or pointer type
error C2227: left of '->Display' must point to class/struct/union
error C2143: syntax error : missing ';' before '}'
error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : error C2143: syntax error : missing ';' before '}'
C:\Documents and Settings\ashida\My Documents\MASTER C++\main\78.cpp(22) : fatal error C1003: error count exceeds 100; stopping compilation
Error executing cl.exe.
78.exe - 102 error(s), 0 warning(s)
Joatmon
0
Junior Poster in Training
Can you post your source now please? (and edit out the big error list, it is mostly the same error over and over again and is just a big waste of space)
I will see what you have and try to help you out.
nurulshidanoni
-1
Posting Whiz in Training
Here it is..
#include <iostream>
usingnamespace std;
{
const int students.size = 12;
Pair<int> * pairs[students.size]; // Declare an array of pointers to Pair<int>
for (int i = 0; i < students.size; i++)
pairs[i] = new Pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array
pairs[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function
return 0;
}
Joatmon
0
Junior Poster in Training
1.
Did you make sure you kept what you had in front of main? I remove that from the code i posted as it is the same as you had, only the things in main were what i changed.
2.
students.size is referring to a data member of an object that doesn't exist. Moreover, since it would be a data member inside an object, it couldn't be declared again. Use a plain variable name instead of students.size. maybe students_size
nurulshidanoni
-1
Posting Whiz in Training
This is a full code. but error.fatal error C1003: error count exceeds 100; stopping compilation
Error executing cl.exe.
is it cannot exceed 100?
/*------------------------------------------------------------------------------------------+
| Filename : ConflictMatrix.cpp |
+------------------------------------------------------------------------------------------*/
#include <iostream> // std::cout
#include <fstream>
#include <iomanip>
#include <string> // std::string
#include <vector> // std::vector<>
#include <algorithm> //std::for each()
using namespace std; // import "std" namespace into global namespace
struct student
{
string studentid;
vector <int> examcode;
};
int main()
{
ifstream stream1 ("STA83STU.txt");
if ( !stream1 )
{
cout << "While opening a file an error is encountered" << endl;
}
else
{
cout << "File is successfully opened" << endl;
}
vector <student> students;
student aStudent;
string tempStudentID;
bool readEntireFile = false; // set to true when reach end of file
stream1 >> tempStudentID; // read in student id of first student
while ( !readEntireFile )
{
aStudent.studentid = tempStudentID; // new student
int tempExamCode;
aStudent.examcode.clear ();
stream1 >> tempExamCode; // read in first exam code for this student
aStudent.examcode.push_back (tempExamCode); // add this exam code to current student's vector of exam codes
bool newStudent = false; // true when a new student id is encountered
while ( !newStudent && !readEntireFile )
{
if ( stream1 >> tempStudentID ) // successfully read in student id
{
if ( tempStudentID.compare (aStudent.studentid) == 0 ) // student id is same as before
{
stream1 >> tempExamCode; // read in exam code
aStudent.examcode.push_back (tempExamCode); // add this exam code to this student;s vector of exam codes
}
else
newStudent = true; // student id is different from before. Therefore new student.
}
else
readEntireFile = true; // end of file reached. Want to exit inner and outer while loops
} // if new student, do not repeat this while loop
students.push_back (aStudent); // no more exam codes for this student. Add aStudent to students vector
}
stream1.close (); // We have read the entire file, so time to close it.
for ( int i = 0 ; i < students.size (); i++ )
{
cout <<i<<":\t" ; // output student id
for ( int j = 0;j<students.at(i).examcode.size(); j++ )
cout << students.at (i).examcode.at(j) <<"\t"; // output list of exam codes for this student
cout<<""<<"\n";
}
/*--------------------------------------------------------------------------------------------+
| counting elements in StudentID |
+--------------------------------------------------------------------------------------------*/
{
const int student_size = 12;
Pair<int> * pairs[student_size]; // Declare an array of pointers to Pair<int>
for (int i = 0; i < student_size; i++)
pairs[i] = new Pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array
pairs[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function
return 0;
}
/*-------------------------------------------------------------------------------------------+
| Matrix ExamID
+--------------------------------------------------------------------------------------------*/
{
cout<<"i,j|";
for (int colHead = 1; colHead < 11; colHead++)
cout << setw(3) << colHead;
cout << endl;
cout <<"__________________________________"<<endl;
for (int rowVal = 1; rowVal < 11; rowVal++)
{
cout << setw(3)<< rowVal <<'|';
for (int colVal =1; colVal < 11; colVal++)
cout << setw(3)<<"x";
cout <<endl;
}
}
}
nurulshidanoni
-1
Posting Whiz in Training
What is the class of Display?
error C2061: syntax error : identifier 'pair'
error C2109: subscript requires array or pointer type
error C2227: left of '->Display' must point to class/struct/union
{
int pair;
const int student_size = 12;
pair <int> * pair[student_size]; // Declare an array of pointers to Pair<int>
for (int i = 0; i < student_size; i++);
{
pair[i] = new pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array
pair[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function
}
return 0;
}
Ancient Dragon
5,243
Achieved Level 70
Team Colleague
Featured Poster
What is the class of Display?
error C2061: syntax error : identifier 'pair'
error C2109: subscript requires array or pointer type
error C2227: left of '->Display' must point to class/struct/union{ int pair; const int student_size = 12; pair <int> * pair[student_size]; // Declare an array of pointers to Pair<int> for (int i = 0; i < student_size; i++); { pair[i] = new pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array pair[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function } return 0; }
delete line 3 because it hids the c++ class by the same name.
nurulshidanoni
-1
Posting Whiz in Training
error C2976: 'pair' : too few template arguments
see declaration of 'pair'
Why there is too few template arguments when i delete line 3?
Ancient Dragon
5,243
Achieved Level 70
Team Colleague
Featured Poster
nurulshidanoni
-1
Posting Whiz in Training
So, I put put like this?
{
typedef std::pair<int,int> RandomPair;
typedef std::vector<RandomPair> VectorRandomPair;
const int student_size = 12;
pair <int> * pair[student_size]; // Declare an array of pointers to Pair<int>
for (int i = 0; i < student_size; i++)
pair[i] = new pair<int>(1,i); // Construct each new pair and give its address to an index in the pointer array
pair[3]->Display(); //since Display is a member function of an object, and pairs[num] is a pointer to that object, you use the arrow operator to dereference and call the member function
return 0;
}
Ancient Dragon
5,243
Achieved Level 70
Team Colleague
Featured Poster
Here is a pretty good explaination of pair. As its name implies, and that link explicitly states, pair required two objects, not one as you have on line 7 And you can not have the name of the array the same as the class name -- the array name must be something else.
const int student_size = 12;
pair<int,int>* array[student_size];
for (int i = 0; i < student_size; i++)
array[i] = new pair<int,int>(1,i); // Construct each new pair and give its address to an index in the pointer arrayI didn't compile or test the above, so use it at your own risk.
nurulshidanoni
-1
Posting Whiz in Training
Thank you ancient dragon. It succefully work out!!!!
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