C++ Programming Code Examples
C++ > Data Structures Code Examples
Program for Multiplication of two matrices using OOP concept
/* Program for Multiplication of two matrices using OOP concept */
#include<iostream.h>
#include<conio.h>
class matrix
{
int a[10][10], m,n;
public:
matrix()
{
}
matrix(int m,int n)
{
this->m=m;
this->n=n;
}
void set_mat()
{
for(int i=0;i<m;i++)
for(int j=0;j<n;j++)
a[i][j]=0;
}
void read_mat();
void disp_mat();
void mul_mat(matrix,matrix);
};
void matrix :: read_mat()
{
for(int i=0;i<m;i++)
for(int j=0;j<n;j++)
{
cout<<"enter element "<<i+1<<","<<j+1<<"?";
cin>>a[i][j];
}
}
void matrix :: disp_mat()
{
cout<<"Matrix Elements:
";
for(int i=0;i<m;i++)
{
for(int j=0;j<n;j++)
cout<<a[i][j]<<" ";
cout<<endl;
}
}
void matrix :: mul_mat(matrix m1,matrix m2)
{
if(m1.n!=m2.m)
cout<<"matrix multiplication is not possible ";
else
{
for(int i=0;i<m1.m;i++)
for(int j=0;j<m1.n;j++)
for(int k=0;k<m2.n;k++)
{
a[i][j]+=m1.a[i][k]*m2.a[k][j];
}
}
}
void main()
{
int m,n,p,q;
clrscr();
cout<<"enter first matrix size ?";
cin>>m>>n;
matrix m1(m,n);
m1.read_mat();
cout<<"enter second matrix size ?";
cin>>p>>q;
matrix m2(p,q);
m2.read_mat();
matrix m3(m,q);
m3.set_mat();
m3.mul_mat(m1,m2);
m1.disp_mat();
m2.disp_mat();
m3.disp_mat();
getch();
}
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The cout is a predefined object of ostream class. It is connected with the standard output device, which is usually a display screen. The cout is used in conjunction with stream insertion operator (<<) to display the output on a console. On most program environments, the standard output by default is the screen, and the C++ stream object defined to access it is cout. The "c" in cout refers to "character" and "out" means "output". Hence cout means "character output". The cout object is used along with the insertion operator << in order to display a stream of characters.
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A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.
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As the name already suggests, these operators help in assigning values to variables. These operators help us in allocating a particular value to the operands. The main simple assignment operator is '='. We have to be sure that both the left and right sides of the operator must have the same data type. We have different levels of operators. Assignment operators are used to assign the value, variable and function to another variable. Assignment operators in C are some of the C Programming Operator, which are useful to assign the values to the declared variables. Let's discuss the various types of the assignment operators such as =, +=, -=, /=, *= and %=. The following table lists the assignment operators supported by the C language:
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