Submission #962267

#	Time	Username	Problem	Language	Result	Execution time	Memory
962267		danikoynov	Art Class (IOI13_artclass)	C++14	67 / 100	54 ms	9728 KiB

artclass

#include "artclass.h"
#include<bits/stdc++.h>
using namespace std;

struct pixel
{
    double r, g, b;
    pixel(double _r = 0.0, double _g = 0.0, double _b = 0.0)
    {
        r = _r;
        g = _g;
        b = _b;
    }
};

//pixel avg_st[5];
pixel image[510][510];
int h, w;

pixel avg_dev[5];

void init()
{
    //   avg_st[1] = pixel(189.852, 166.758, 147.354);
    // avg_st[2] = pixel(102.854, 98.1113, 64.2302);
    // avg_st[3] = pixel(140.586, 128.459, 107.031);
    // avg_st[4] = pixel(158.108, 89.7725, 55.3149);

    avg_dev[1] = pixel(2288.99, 2322.12, 2839.83);
    avg_dev[2] = pixel(749.693, 627.756, 424.602);
    avg_dev[3] = pixel(2897.08, 2767.16, 2537.68);
    avg_dev[4] = pixel(169.811, 143.836, 248.756);
}

double penalty[5];

pixel average_pixel(int stx, int sty, int enx, int eny)
{
    double sr = 0.0;
    double sg = 0.0;
    double sb = 0.0;

    for (int i = stx; i <= enx; i ++)
        for (int j = sty; j <= eny; j ++)
        {
            sr += image[i][j].r;
            sg += image[i][j].g;
            sb += image[i][j].b;
        }

    double cnt = (enx - stx + 1) * (eny - sty + 1);
    sr /= cnt;
    sg /= cnt;
    sb /= cnt;
    return pixel(sr, sg, sb);
}

pixel region_deviation(int stx, int sty, int enx, int eny)
{
    pixel avg = average_pixel(stx, sty, enx, eny);

    double dr = 0.0;
    double dg = 0.0;
    double db = 0.0;

    for (int i = stx; i <= enx; i ++)
    {
        for (int j = sty; j <= eny; j ++)
        {
            double delta_red = abs(image[i][j].r - avg.r);
            double delta_green = abs(image[i][j].g - avg.g);
            double delta_blue = abs(image[i][j].b - avg.b);

            delta_red = delta_red * delta_red;
            delta_green = delta_green * delta_green;
            delta_blue = delta_blue * delta_blue;

            dr += delta_red;
            dg += delta_green;
            db += delta_blue;
        }
    }

    double cnt = (enx - stx + 1) * (eny - sty + 1);

    dr /= cnt;
    dg /= cnt;
    db /= cnt;

    return pixel(dr, dg, db);
}

const int block = 20;
pixel get_average_block_deviation()
{
    pixel avg;
    double cnt = 0.0;
    for (int i = 0; i < h; i += block)
        for (int j = 0; j < w; j += block)
        {
            int stx = i, sty = j;
            int enx = min(h, i + block) - 1;
            int eny = min(w, j + block) - 1;


            pixel cur = region_deviation(stx, sty, enx, eny);
            for (int s = 1; s <= 4; s ++)
            {
                double dr = abs(cur.r - avg_dev[s].r);
                double dg = abs(cur.g - avg_dev[s].g);
                double db = abs(cur.b - avg_dev[s].b);

                dr = dr * dr;
                dg = dg * dg;
                db = db * db;
                penalty[s] += dr + dg + db;
            }

            avg.r += cur.r;
            avg.g += cur.g;
            avg.b += cur.b;
            cnt ++;
        }

    avg.r /= cnt;
    avg.g /= cnt;
    avg.b /= cnt;
    return avg;
    //cout << "average deviation" << endl;
    //cout << avg.r << " " << avg.g << " " << avg.b << endl;
}

int style(int H, int W, int R[500][500], int G[500][500], int B[500][500])
{
    init();
    h = H;
    w = W;
    for (int i = 0; i < h; i ++)
        for (int j = 0; j < w; j ++)
        {
            image[i][j] = pixel(R[i][j], G[i][j], B[i][j]);
        }

    pixel dev = get_average_block_deviation();

    int mx = 1;
    for (int i = 1; i <= 4; i ++)
    {
        if (penalty[i] < penalty[mx])
            mx = i;
    }
    return mx;
}

Compilation message (stderr)

artclass.cpp: In function 'int style(int, int, int (*)[500], int (*)[500], int (*)[500])':
artclass.cpp:144:11: warning: variable 'dev' set but not used [-Wunused-but-set-variable]
  144 |     pixel dev = get_average_block_deviation();
      |           ^~~

• Subtask 1: 67 / 100