C++ Programming Code Examples
C++ > Beginners Lab Assignments Code Examples
This is a program of matrix capable of doing several works with two matrices.
/* This is a program of matrix capable of doing several works with two matrices.
It can add, subtract, multiply of two matrices and
if user wants to see the input entered in two matrices he can also see. It
provides the facility to user to do again some work on another matrix
without running the program twice. */
#include<iostream.h>
#include<conio.h>
#include<iomanip.h>
#include<process.h>
#define sk 100
class matrix
{
public:
int i,j,k,sum,r1,r2,c1,c2;
int m1[sk][sk],m2[sk][sk];
char reply;
void getin(void);
void mply(void);
void add(void);
void minus(void);
void read(void);
void input(void);
};
void matrix::getin()
{
cout<<"
WELCOME TO SOLUTION OF TWO MATRICRES ";
cout<<"
-------------------------------------";
cout<<"
YOU CAN CALCULATE UPTO A LIMIT OF MATRIX 100 * 100 ";
cout<<"
YOU CAN DO THE FOLLOWING :
ADDITION
SUBTRACTION
";
cout<<"
MULTIPLICATION AND
READ ONLY ";
cout<<"
DO YOU WANT TO CONTINUE [Y/N] : ";
cin >>reply;
if(reply=='y'||reply=='Y')
{
cout<<"
Enter the number of rows and columns of matrix 1 : ";
cin>>r1>>c1;
cout<<"
Enter the value of matrix 1 : "<<endl;
for(i=0;i<r1;i++)
for(j=0;j<c1;j++)
cin>>m1[i][j];
cout<<"
Enter the number of rows and columns of matrix 2 : ";
cin>>r2>>c2;
cout<<"
Enter the value of matrix 2 : "<<endl;
for(i=0;i<r2;i++)
for(j=0;j<c2;j++)
cin>>m2[i][j];
}
else exit(0);
}
void matrix::mply()
{
cout<<"
THE RESULT AFTER MULTIPLICATION IS :
";
if(c1==r2)
{
for(i=0;i<r1;i++)
{
cout<<endl;
for(j=0;j<c2;j++)
{
sum=0;
for(k=0;k<c1;k++)
sum+=m1[i][k]*m2[k][j];
cout<<setw(6)<<sum;
}
}
}
else
{
cout<<"
INVALID INPUT ";
cout<<"
MULTIPLICATION NOT POSSIBLE ";
}
}
void matrix::add()
{
cout<<"
THE RESULT AFTER ADDITION IS :
";
if(r1==r2&&c1==c2)
{
for(i=0;i<r1;i++)
{
cout<<endl;
for(j=0;j<c1;j++)
cout<<setw(3)<<(m1[i][j]+m2[i][j]);
}
}
else
{
cout<<"
INVALID INPUT ";
cout<<"
ADDITION NOT POSIIBLE ";
}
}
void matrix::minus()
{
cout<<"
THE RESULT AFTER SUBTRACTION IS :
";
if(r1==r2&&c1==c2)
{
for(i=0;i<r1;i++)
{
cout<<endl;
for(j=0;j<c1;j++)
cout<<setw(3)<<(m1[i][j]-m2[i][j]);
}
}
else
{
cout<<"
INVALID INPUT ";
cout<<"
SUBTRACTION NOT POSSIBLE ";
}
}
void matrix::read()
{
cout<<"
ENTERED MATRIX 1 IS :
";
for(i=0;i<r1;i++)
{
cout<<endl;
for(j=0;j<c1;j++)
cout<<setw(3)<<m1[i][j];
}
cout<<endl;
cout<<"
ENTERED MATRIX 2 IS :
";
for(i=0;i<r2;i++)
{
cout<<endl;
for(j=0;j<c2;j++)
cout<<setw(3)<<m2[i][j];
}
}
void main()
{
int ans,option;
char response;
matrix m;
clrscr();
start :
m.getin();
again :
cout<<"
What you wish to do : "<<endl;
cout<<"
1.ADDITION ";
cout<<"
2.SUBTRACTION ";
cout<<"
3.MULTIPLY ";
cout<<"
4.READ ONLY ";
cout<<"
5.EXIT ";
cout<<"
ENTER YOUR CHOICE IN NUMBERS : ";
repeat :
cin>>ans;
switch(ans)
{
case 1 : m.add(); break;
case 2 : m.minus(); break;
case 3 : m.mply(); break;
case 4 : m.read(); break;
case 5 : goto exit ;
default :
{
cout<<"
INVALID ENTRY
ENTER YOUR CHOICE AGAIN : ";
goto repeat;
}
}
cout<<"
DO YOU WANT TO DO IT FOR ANOTHER TIME [Y/N] : ";
cin>>response;
if(response=='y'||response=='Y')
{
wrong:
cout<<"
Enter your choice in number
";
cout<<"
1.FOR Same matrix
2.FOR Another matrix
";
cin>>option;
switch(option)
{
case 1 : goto again;
case 2 : goto start;
default: cout<<"
INVALID ENTRY "; goto wrong;
}
}
exit :
getch();
}
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
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The getch() is a predefined non-standard function that is defined in conio.h header file. It is mostly used by the Dev C/C++, MS- DOS's compilers like Turbo C to hold the screen until the user passes a single value to exit from the console screen. It can also be used to read a single byte character or string from the keyboard and then print. It does not hold any parameters. It has no buffer area to store the input character in a program. The getch() function does not accept any parameter from the user. It returns the ASCII value of the key pressed by the user as an input.
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It is a predefined function in "conio.h" (console input output header file) used to clear the console screen. It is a predefined function, by using this function we can clear the data from console (Monitor). Using of clrscr() is always optional but it should be place after variable or function declaration only. It is often used at the beginning of the program (mostly after variable declaration but not necessarily) so that the console is clear for our output.
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