C++ Programming Code Examples
C++ > Data Structures Code Examples
C++ Program to Implement Sparse Matrix
/* C++ Program to Implement Sparse Matrix
This C++ Program demonstrates the implementation of Sparse Matrix. */
#include <iostream>
#include <iomanip>
#include <string>
using namespace std;
/* Class List Declaration */
class List
{
private:
int index;
int value;
List *nextindex;
public:
List(int index)
{
this->index = index;
nextindex = NULL;
value = NULL;
}
List()
{
index = -1;
value = NULL;
nextindex = NULL;
}
void store(int index, int value)
{
List *current = this;
List *previous = NULL;
List *node = new List(index);
node->value = value;
while (current != NULL && current->index < index)
{
previous = current;
current = current->nextindex;
}
if (current == NULL)
{
previous->nextindex = node;
}
else
{
if (current->index == index)
{
cout<<"duplicate index"<<endl;
return;
}
previous->nextindex = node;
node->nextindex = current;
}
return;
}
int fetch(int index)
{
List *current = this;
int value = NULL;
while (current != NULL && current->index != index)
{
current = current->nextindex;
}
if (current != NULL)
{
value = current->value;
}
else
{
value = NULL;
}
return value;
}
int elementCount()
{
int elementCount = 0;
List *current = this->nextindex;
for ( ; (current != NULL); current = current->nextindex)
{
elementCount++;
}
return elementCount;
}
};
/* Class SpareArray Declaration */
class SparseArray
{
private:
List *start;
int index;
public:
SparseArray(int index)
{
start = new List();
this->index = index;
}
void store(int index, int value)
{
if (index >= 0 && index < this->index)
{
if (value != NULL)
start->store(index, value);
}
else
{
cout<<"index out of bounds"<<endl;
}
}
int fetch(int index)
{
if (index >= 0 && index < this->index)
return start->fetch(index);
else
{
cout<<"index out of bounds"<<endl;
return NULL;
}
}
int elementCount()
{
return start->elementCount();
}
};
/* Class SparseMatrix Declaration */
class SparseMatrix
{
private:
int N;
SparseArray **sparsearray;
public:
SparseMatrix(int N)
{
this->N = N;
sparsearray = new SparseArray* [N];
for (int index = 0; index < N; index++)
{
sparsearray[index] = new SparseArray(N);
}
}
void store(int rowindex, int colindex, int value)
{
if (rowindex < 0 || rowindex > N)
{
cout<<"row index out of bounds"<<endl;
return;
}
if (colindex < 0 || colindex > N)
{
cout<<"col index out of bounds"<<endl;
return;
}
sparsearray[rowindex]->store(colindex, value);
}
int get(int rowindex, int colindex)
{
if (rowindex < 0 || colindex > N)
{
cout<<"row index out of bounds"<<endl;
return 0;
}
if (rowindex < 0 || colindex > N)
{
cout<<"col index out of bounds"<<endl;
return 0;
}
return (sparsearray[rowindex]->fetch(colindex));
}
int elementCount()
{
int count = 0;
for (int index = 0; index < N; index++)
{
count += sparsearray[index]->elementCount();
}
return count;
}
};
/* Main */
int main()
{
int iarray[3][3];
iarray[0][0] = 1;
iarray[0][1] = NULL;
iarray[0][2] = 2;
iarray[1][0] = NULL;
iarray[1][1] = 3;
iarray[1][2] = NULL;
iarray[2][0] = 4;
iarray[2][1] = 6;
iarray[2][2] = NULL;
SparseMatrix sparseMatrix(3);
for (int rowindex = 0; rowindex < 3; rowindex++)
{
for (int colindex = 0; colindex < 3; colindex++)
{
sparseMatrix.store(rowindex, colindex, iarray[rowindex][colindex]);
}
}
cout<<"the sparse Matrix is: "<<endl;
for (int rowindex = 0; rowindex < 3; rowindex++)
{
for (int colindex = 0; colindex < 3; colindex++)
{
if (sparseMatrix.get(rowindex, colindex) == NULL)
cout<<"NULL"<< "\t";
else
cout<<sparseMatrix.get(rowindex, colindex) << "\t";
}
cout<<endl;
}
cout<<"The Size of Sparse Matrix is "<<sparseMatrix.elementCount()<<endl;
}
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