multiplication of two matrices in c++

#include<iostream.h>
#include<conio.h>
void main()
{

int r1,r2,c1,c2,i,j,k;
int ham[12][12];
int tum[12][12];
int mul[12][12]={0,0,0,0,0,0,0,0,0,0,0,0};

        cout<<"enter no of row of first matrix         ";
        cin>>r1;
        cout<<"enter no of columns of first matrix     ";
        cin>>c1;
        cout<<endl<<"enter no of row of 2nd  matrix          ";
        cin>>r2;
        cout<<"enter no of columns of 2nd matrix       ";
        cin>>c2;

if(c1==r2)
{
     cout<<"\n\n";
     for(i=0;i<r1;i++)
     for(j=0;j<c1;j++)
     {cout<<"ham["<<i<<"]["<<j<<"]"<<"\t" ;
     cin>>ham[i][j];}

     cout<<"\n\n";
     for(i=0;i<r2;i++)
     for(j=0;j<c2;j++)
     {cout<<"tum["<<i<<"]["<<j<<"]"<<"\t";
     cin>>tum[i][j];}

     cout<<"\n\n";
     cout<<"MULTIPLICATION OF THE MATRICES IS"<<endl<<endl;
             for(i=0;i<r1;i++)              //control no of rows
         {for(j=0;j<c2;j++)             //control no of columns
         {for(k=0;k<c1;k++)             //control two parts of each member
         mul[i][j]=mul[i][j]+ham[i][k]*tum[k][j];
         cout<<mul[i][j]<<"\t";}
         cout<<endl;}


     }                                                                          //end of if
else
     cout<<"matrices are not in order";




    getch();
}                                                                            //end of main body