floye Steinberg

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


int main()
{
    float arr[3][3] = {{1,32,120},{132,252,18},{80,140,255}};

    float error[3][3]= {};
    int step  = 1;
    for(int i=0; i<3; i++)
    {
        for(int j=0; j<3; j++)
        {
            cout << endl << endl;
            cout << "Step : " << step << endl;
            float pixel = arr[i][j];
            // cout << "Old Pixel: " << pixel << endl;
            printf("Old Pixel : %.0f \n",pixel);
            float newPixel;
            //if(pixel < 128) newPixel = 0;
            if(pixel < 85)
                newPixel = 0;
            else if(pixel < 170)
                newPixel = 128;
            else
                newPixel = 255;
            // cout << "New Pixel : " << newPixel << endl;
            printf("New Pixel : %.0f \n",newPixel);
               if(arr[i][j] < 85)
                    arr[i][j] = 0;
                else if(arr[i][j] < 170)
                    arr[i][j] = 128;
                else
                    arr[i][j] = 255;
            float err = pixel - newPixel;
            if(i==0&j==0)
                error[0][0] = err;
            if(j<2)
            {
                printf("position (%d,%d),newPixel value : %.0f + %.0f * 7/16 = %.0f \n",i,j+1,arr[i][j+1],err,arr[i][j+1]+err*(7.0/16.0));
                arr[i  ][j+1]+=err*(7.0/16.0);

                error[i][j+1] = pixel - abs(err*(7.0/16.0));
            }
            if(i<2)
            {
                printf("position (%d,%d),newPixel value : %.0f + %.0f * 5/16 = %.0f \n",i+1,j,arr[i+1][j],err,arr[i+1][j]+err*5/16);
                arr[i+1][j  ]+=err*5/16;

                error[i+1][j  ]=pixel - abs(err*(5.0/16.0));
            }
            if(i<2 && j>0)
            {
                printf("position (%d,%d),newPixel value : %.0f + %.0f * 3/16 = %.0f \n",i+1,j-1,arr[i+1][j-1],err,arr[i+1][j-1]+err*3/16);

                arr[i+1][j-1]+=err*3/16;

                error[i+1][j-1]=pixel - abs(err*(3.0/16.0));
            }
            if(i<2&&j<2)
            {
                printf("position (%d,%d),newPixel value : %.0f + %.0f * 1/16 = %.0f \n",i+1,j+1,arr[i+1][j+1],err,arr[i+1][j+1]+err*1/16);

                arr[i+1][j+1]+=err*1/16;
                error[i+1][j+1]=pixel - abs(err*(1.0/16.0));

            }

            cout << "Array updated : " << endl;

            for(int x=0; x<3; x++)
            {
                for(int y=0; y<3; y++)
                {
                    float pixel = arr[x][y];
                    printf("%.0f ",pixel);
                }
                cout << endl;
            }
            /*
            cout << "Array error : " << endl;
            for(int x=0; x<3; x++)
            {
                for(int y=0; y<3; y++)
                {
                    float pixel = error[x][y];
                    printf("%.2f ",pixel);
                }
                cout << endl;
            }
            */
            step++;
        }
    }
}