Fraktaali

input/code.cpp: In function 'Fractal* make_fractal(int)':
input/code.cpp:49:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

#include <iostream>
#include <cmath>
#include <vector>

//Canvas where we'll draw the fractals.
std::vector<std::vector<bool>> canvas;

//W is the width of the fractal in characters, global of simplicity's sake
int w;


struct Fractal{
    //Upper left, upper right, lower left, lower right. These are nullprts if the fractal is a leaf node in the tree
    Fractal *l1, *r1, *l2, *r2;
    
    //False='#', true='.'
    bool flipped;
    void flip(){
        flipped = !flipped;
         if(l1){
             l1->flip(); r1->flip(); l2->flip(); r2->flip(); 
            }
        }
};

//Creates a fractal of dimension n
Fractal* make_fractal(int n){
    Fractal* frac = new Fractal;
    frac->flipped = false;


    if(n == 1){
        frac->l1 = frac->r1 = frac->l2 = frac->r2 = nullptr;
        return frac;
    }
   
    if(n != 1){
        n--;
        //Optimization, 3 out of 4 fractals are the same so why use the memory 
        frac->l1 = frac->r1 = frac->l2 = make_fractal(n);
      //  frac->r1 = make_fractal(n);
      //  frac->l2 = make_fractal(n);
        frac->r2 = make_fractal(n);
        frac->r2->flip();
        return frac;

    }
   
}


//Draws a character onto the canvas, the coordinate system uses the bottom left corner as origin
void draw(int x, int y, bool flipped){
    canvas[w - y - 1][x] = flipped;

};

//Draws a fractal. Works by calling itself on all of the fractal's components, and shrinking the area where the fractal is.
//x1 and x2 are the minimum and maximum coordinates of the fractal, they get smaller when one goes deeper into the fractal, until they hit equality at the leaf node
//y1 and y2 work the same way
void drawFractal(Fractal* frac, int x1, int x2, int y1, int y2){
  
    if(frac->l1 != nullptr)
    {
        drawFractal(frac->l1, x1, x1 + (x2-x1+1)/2-1,     y1 + (y2-y1+1)/2, y2);
        drawFractal(frac->r1, x1 + (x2-x1+1)/2, x2, y1 + (y2-y1+1)/2, y2);
        drawFractal(frac->l2, x1, x1 + (x2-x1+1)/2,      y1, y1 + (y2-y1+1)/2);
        drawFractal(frac->r2, x1 + (x2-x1+1)/2, x2,  y1, y1 + (y2-y1+1)/2);
    }
    else{
        draw(x1, y1, frac->flipped);
    }

}

int main(){
    int n;

    std::cin >> n;

    w = pow(2, n - 1);
    
    //Init the canvas
    for(int i = 0; i < w; i++){
        canvas.push_back(std::vector<bool>(w));
    }
    
    //Make the fractal
    Fractal* frac = make_fractal(n);

    //Draw the fractal onto the canvas, use the full canvas for the first coordinates
    drawFractal(frac, 0, w-1, 0, w-1 );

    //Finally output the canvas
    for(int y = 0; y < w; y++){
        for(int x = 0; x < w; x++){
            std::cout << (canvas[y][x] ? "." : "#");
        }
        std::cout << "\n";
    }
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 3

Verdict: ACCEPTED

Test 4

Group: 4

Verdict: ACCEPTED

Test 5

Group: 5

Verdict: ACCEPTED

Test 6

Group: 6

Verdict: ACCEPTED

Test 7

Group: 7

Verdict: ACCEPTED

Test 8

Group: 8

Verdict: ACCEPTED

Test 9

Group: 9

Verdict: ACCEPTED

Test 10

Group: 10

Verdict: ACCEPTED