c program matrix multiplication using arrays

For beginners
{I am going write the c program but before you need a c compiler(software).there are a lot of compilers(software) for windows 7  like Code::Blocks,dev c++ . Download dev c++ its free and install it in your computer.open  dev c++ go to file-->new-->source file.}  


#include<stdio.h>
#include<conio.h>
main()
{
    int m1[20][20],m2[20][20],mult[20][20],i,j,k,r1,c1,r2,c2;
    printf("Enter number of rows and columns of first matrix (less than 20)\n");
    scanf("%d%d",&r1,&c1);
    printf("Enter number of rows and columns of second matrix (less than 20)\n");
    scanf("%d%d",&r2,&c2);
    if(r2==c1)
    {
        printf("Enter the First matrix \n");
        printf("enter the numbers in Row wise\n");
        for(i=0;i<r1;i++)
            for(j=0;j<c1;j++)
                scanf("%d",&m1[i][j]);
        printf("First Matrix is :\n");
        for(i=0;i<r1;i++)
        {
            for(j=0;j<c1;j++)
                printf("%d\t",m1[i][j]);
            printf("\n");
        }
        printf("Enter the Second matrix \n");
        printf("enter the numbers in Row wise\n");
        for(i=0;i<r2;i++)
            for(j=0;j<c2;j++)
                scanf("%d",&m2[i][j]);
        printf("Second Matrix is:\n");
        for(i=0;i<r2;i++)
        {
            for(j=0;j<c2;j++)
                printf("%d\t",m2[i][j]);
            printf("\n");
        }
        printf("product of the Matrices is:\n");
        for(i=0;i<r1;i++)
        {
            for(j=0;j<c2;j++)
            {
                mult[i][j]=0;
                for(k=0;k<r1;k++)
                    mult[i][j]+=m1[i][k]*m2[k][j];
                printf("%d\t",mult[i][j]);
            }
            printf("\n");
        }
    }
    else
    {
        printf("Matrix multiplication cannot be done");
    }
    getch();
    return 0;
}

For beginners

{After typing this program go to execute-->compile & run-->a window will pop-up-->give file name:(anything u like)-->save as type: c source files-->click save.}

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