#include <iostream>
#include <thread>
#include <cmath>
#include <vector>
 
using namespace std;
 
const int N=1024;
const int level=8;
 
unsigned char tab[1024][1024][3];
 
void triangle(int lvl, int x, int y) {
    int size=N/pow(2,lvl);
 
    for(int i=0;i<size;i++)//pionowe //wysokosc = y
        for (int j=0;j<size;j++)//poziome // szerokosc = x
            if (i == j || i == 0 || j == size - 1) 
                for (int k=0;k<3;k++)
                {
                	tab[j + x][i + y][k] = 0;
                	tab[i + y][j + x][k] = 0;
                }
 
    if(lvl<level) 
    {
        vector<thread> v;
        v.push_back(thread(triangle, lvl + 1, x + size / 2, y));
        v.push_back(thread(triangle, lvl + 1, x, y));
        v.push_back(thread(triangle, lvl + 1, x + size / 2, y + size / 2));
 
 
     for (int i = 0; i < v.size(); i++)
            v[i].join();
	}
}
 
int main() {
	 for(int i=0;i<N;i++)
        for (int j=0;j<N;j++)
        	for (int k=0;k<3;k++)
				tab[j][i][k] = 255;
    triangle(0, 0, 0);
    FILE *fp = fopen("39247_lab3.ppm", "wb");
    fprintf(fp, "P6n %sn %dn %dn %dn", " #", N, N, 255);
    for (int i = 0; i < N; i++) 
        for (int j = 0; j < N; j++) 
            fwrite(tab[i][j], 1, 3, fp);
    fclose(fp);
    return 0;
}