Sparse Matrix Multiplication in CPP

Hi GuyZ,
     This is a simple programming problem asked during your BCA/MCA/B.Tech Data Structures and Algorithms paper.

Source Code

#include <iostream>
#include <stdlib.h>
using namespace std;
/*
    Coded By Ajith Kp [ ajithkp560 ]
    (c) _TERMINAL_CODERS http://www.terminalcoders.blogspot.com (c)
*/
struct tripp
{
 int r, c, v;
};
class sparse
{
 int i, j, k, cc, cr, crb, sum, f[1024], pc[1024];
 public:
 tripp a[1024], b[1024];
 void read()
 {
  cout<<"Enter r, c & v: ";
  cin>>a[0].r>>a[0].c>>a[0].v;
  for(i=1;i<=a[0].v;i++)
  {
   cin>>a[i].r>>a[i].c>>a[i].v;
  }
 }
 void show()
 {
  k = 1;
  for(i=0;i<a[0].r;i++)
  {
   for(j=0;j<a[0].c;j++)
   {
    if(a[k].r==i && a[k].c==j)
    {
     cout<<a[k++].v<<"\t";
    }
    else cout<<"0\t";
   }
   cout<<"\n";
  }
 }
 void sort()
 {
     b[0] = a[0];
  for(i=0;i<a[0].c;i++)f[i] = 0;
  for(i=1;i<=a[0].v;i++)f[a[i].c]++;
  pc[0] = 1;
  for(i=1;i<a[0].c;i++)pc[i]=f[i-1]+pc[i-1];
  for(i=1;i<=a[0].v;i++)
  {
   b[pc[a[i].c]] = a[i];
   pc[a[i].c]++;
  }
 }
 sparse operator*(sparse sp)
 {
  if(a[0].c!=sp.b[0].r)
  {
   cout<<"Cannot perform operation\n";
   exit(0);
  }
  sparse s;
  k=1;
     i=1; 
     s.a[0].r = a[0].r;
     s.a[0].c = sp.b[0].c;
     while(i<=a[0].v) 
     {
         crb=i; 
         j=1; 
         while(j<=sp.b[0].v) 
         {
             cr=a[i].r; 
             cc=sp.b[j].c; 
             sum=0; 
 
    while(i<=a[0].v && j<=sp.b[0].v && cr==a[i].r && cc==sp.b[j].c) 
    { 
     if(a[i].c==sp.b[j].r) 
     { 
      sum+=a[i].v*sp.b[j].v; 
      i++;j++; 
     } 
     else if(a[i].c<sp.b[j].r) 
      i++; 
                 else 
                     j++; 
    } 
    if(sum) 
    {
     s.a[k].r=cr; 
     s.a[k].c=cc; 
     s.a[k].v=sum; 
     k++; 
    } 
    i=crb; 
    while(cc==sp.b[j].c) j++; 
   } 
   while(cr==a[i].r)
    i++; 
     } 

  s.a[0].v = k;
  return s;
 }
};
int main()
{
 sparse s1, s2, s3;
 s1.read();
 s2.read();
 cout<<"\nFirst matrix: \n";
 s1.show();
 cout<<"\nSecond Matrix: \n";
 s2.show();
 s2.sort();
 s3=s1*s2;
 cout<<"\n\nResult of multiplication:\n";
 s3.show();
}