Спринт 5. Проблема двойного включения.

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wall.h
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#pragma once

class Wall {
public:
    enum class Color { BLUE, GREEN, RED, WHITE, YELLOW };

    Wall(double width, double height);

    double GetHeight() const;
    double GetWidth() const;
    void SetColor(Color color);
    Color GetColor() const;

private:
    double width_;
    double height_;
    Color color_;
};
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wall.cpp
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#include "wall.h"

Wall::Wall(double width, double height)
    : width_(width)
    , height_(height)
    , color_(Color::WHITE) {
}

double Wall::GetHeight() const {
    return height_;
}
double Wall::GetWidth() const {
    return width_;
}
void Wall::SetColor(Color color) {
    color_ = color;
}
Wall::Color Wall::GetColor() const {
    return color_;
}
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square_calculation.h
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#pragma once

double CalcSquare(double width, double height);

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square_calculation.cpp
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#include "square_calculation.h"

double CalcSquare(double width, double height) {
    return width * height;
}

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painter.h
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#pragma once
#include "square_calculation.h"
#include "wall.h"

class Painter {
public:
    void Paint(Wall& wall, Wall::Color color) const {
        wall.SetColor(color);
    }
    double CalcPaintNeeded(const Wall& wall) const {
        double height = wall.GetHeight();
        double width = wall.GetWidth();
        return CalcSquare(width, height) * 0.4;
    }
};
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main.cpp
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#include <iostream>

#include "builder.h"
#include "carpenter.h"
#include "painter.h"

using namespace std;

int main() {
    Builder tom;
    Painter bill;
    Carpenter jack;
    Wall wall(3.5, 2.45);

    cout << tom.CalcBricksNeeded(wall) << endl;
    cout << bill.CalcPaintNeeded(wall) << endl;
    cout << jack.CalcShelves(wall) << endl;
    return 0;
}
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carpenter.h
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#pragma once
#include "wall.h"

class Carpenter {
public:
    int CalcShelves(const Wall& wall) const;
};
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carpenter.cpp
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#include "carpenter.h"

#include "square_calculation.h"

int Carpenter::CalcShelves(const Wall& wall) const {
    double height = wall.GetHeight();
    double width = wall.GetWidth();
    return CalcSquare(width, height) / 2;
}
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builder.h
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#pragma once
#include "square_calculation.h"
#include "wall.h"

class Builder {
public:
    double CalcBricksNeeded(const Wall& wall) const {
        double height = wall.GetHeight();
        double width = wall.GetWidth();
        return CalcSquare(width, height) * 5;
    }
};