C Programming Code Examples C > Beginners Lab Assignments Code Examples Program to Multiply Two Matrices Program to Multiply Two Matrices #define maxrows 30 #define maxcols 30 void readinput(int a[][maxcols],int m,int n); void computeproduct(int a[][maxcols],int b[][maxcols],int c[][maxcols],int m,int n,int p); void writeoutput(int c[][maxcols],int m,int p); int z=0; void main() { /* char c;*/ int nrows,ncols,mrows,mcols; int a[maxrows][maxcols],b[maxrows][maxcols],c[maxrows][maxcols]; clrscr(); printf(" How many rows in the first matrix? "); scanf("%d",&nrows); printf(" How many cols in the first matrix? "); scanf("%d",&ncols); printf(" How many rows in the second matrix? "); scanf("%d",&mrows); printf(" How many cols in the second matrix? "); scanf("%d",&mcols); if (ncols != mrows) { printf("The product of these matrices is not defined."); getch(); exit(0); } printf(" First table: "); readinput(a,nrows,ncols); printf(" Second table: "); readinput(b,mrows,mcols); computeproduct(a,b,c,nrows,ncols,mcols); printf(" Product of the matrices is: "); writeoutput(c,nrows,mcols); getch(); } void readinput(int a[][maxcols],int m,int n) { int row,col; for (row=0;row<m;row++) { printf(" Enter data for row no. %4d ",row+1); for (col=0;col<n;col++) scanf("%d",&a[row][col]); } z=z+1; printf(" Table %d ",z); for (row=0;row<m;row++) { for (col=0;col<n;col++) printf("%d%c",a[row][col],' '); printf(" "); } return; } void computeproduct(int a[][maxcols],int b[][maxcols],int c[][maxcols],int m,int n,int p) { int i,j,k,sum=0; for (i=0;i<m;i++) { for (j=0;j<p;j++) { for (k=0;k<n;k++) sum=sum+(a[i][k]*b[k][j]); c[i][j]=sum; sum=0; } } return; } void writeoutput(int c[][maxcols],int m,int p) { int row,col; for (row=0;row<m;row++) { for (col=0;col<p;col++) printf("%6d",c[row][col]); printf(" "); } return; }