问题描述

关于稀疏矩阵的问题（#include "source"是要自己写的地方）

Design a class Sparse that implements interface Matrix: Sparse should has the following public object functions in addition:
A constructor Sparse(int rows, int column), which initializes all elements in the matrix to 0's.
A function Sparse Sparse::operator + (Sparse & sparse2), which returns the pair-wise sum of two sparse matrixes.
EXAMPLE INPUT
1000000 1000000

1 1 10
1 1000000 50
1000000 1000000 20

1 1000000 30
1000000 1 40
1 1 -10
EXAMPLE OUTPUT
(1,1000000,80)
(1000000,1,40)
(1000000,1000000,20)

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class Entry
{
public:
int row;
int column;
double value;
};

class Matrix
{

public:
virtual int size(int dimension) const = 0;

virtual void set(int row, int column,
double value) = 0; 

virtual double get(int row, int column)
const = 0; 

virtual void print() = 0;

};

#include "source"

#include
using namespace std;

void print(Matrix & matrix) {
matrix.print();
}

void readAndSetElement(Matrix & matrix) {
int row;
int column;
double value;
cin >> row >> column >> value;
matrix.set(row, column, value);
}

void readAndSetMultipleElements(Matrix & matrix, int count) {
for (int i = 0; i < count; ++ i) {
readAndSetElement(matrix);
}
}

int main() {
int rows;
int columns;
cin >> rows >> columns;

Sparse sparse1(rows, columns);
readAndSetMultipleElements(sparse1, 3); 

Sparse sparse2(rows, columns);
readAndSetMultipleElements(sparse2, 3); 

Sparse sparse3 = sparse1 + sparse2;
print(sparse3);

}

解决方案

#include <iostream>
using namespace std;
#define MAXSIZE 10
class Entry
{
public:
    int row;
    int column;
    double value;
};
class Matrix
{

public:
    virtual int size(int dimension) const = 0;
    virtual void set(int row, int column,
        double value) = 0;

    virtual double get(int row, int column)
        const = 0;

    virtual void print() = 0;
}; 

class Sparse :public Matrix
{
private:
    int _row;
    int _column;
    Entry _data[MAXSIZE];
    int _h = 0;
public:
    int length(){ return _h; }
    Sparse(int row, int column)
    {
        _row = row;
        _column = column;
    }
    virtual int size(int dimension) const
    {
        if (dimension == 0)
            return _row;
        else if (dimension == 1)
            return _column;
        else
            return 1;
    }
    virtual void set(int row, int column, double value)
    {
        bool done = false;
        for (int i = 0; i < _h; i++)
        {
            if (_data[i].row == row && _data[i].column == column)
            {
                _data[i].value = value;
                done = true;
                break;
            }
        }
        if (!done)
        {
            if (_h < MAXSIZE)
            {
                _data[_h].row = row;
                _data[_h].column = column;
                _data[_h].value = value;
                _h++;
            }
            else
                throw;
        }
    }
    virtual double get(int row, int column) const
    {
        for (int i = 0; i < _h; i++)
        {
            if (_data[i].row == row && _data[i].column == column)
            {
                return _data[i].value;
            }
        }
        return 0; }
    virtual void print()
    {
        for (int i = 0; i < _h; i++)
        {
            cout << "(" << _data[i].row << "," << _data[i].column << "," << _data[i].value << ")" << endl;
        }
    }
    Sparse operator +(Sparse another)
    {
        for (int i = 0; i < another._h; i++)
        {
            double v = get(another._data[i].row, another._data[i].column);
            set(another._data[i].row, another._data[i].column, another._data[i].value + v);
        }
        return *this;
    }
};

解决方案二：

size函数是用来返回Dimension的 如果dimension =1就返回rows dimension =2就返回columns