2013 ACM/ICCC Asia Regional Changsha Online–C問題Color Representation Conversion(坑父シミュレーション問題)

标题:RGB、HSV、HSLの3色表示モードを与え、任意のモード間の2つの変換を実現します.
1.テーマの中で与えられた転化公式の説明を見ないほうがいいです.私は叙述の少しもはっきりしないと思います.ウィキペディアを見て、ウィキペディアの公式を一言一言翻訳すればいいと思います.
2.数式換算では、すべて小数に変換します.例えば、RGBの取値範囲0-255は、r=R/255.0、g=G/255.0 b=B/255.0に変換される…
3.HSL->RGBとHSV->RGBは四捨五入する必要があり、HSVとHSLの間の相互変換はRGB:HSV<=>RGB<=>HSLを通過する必要があり、ここでRGBを回すときは四捨五入する必要はない.
4.自分で自分を回す場合、例えばRGBB->RGBはそのまま出力します.
書くときは頭がよくわからないし、WAを付けてからいろいろ変えて、コードが少しブス==間に合わせに見ましょう・・・

#include <cstdio>

#include <cstring>

#include <cstdlib>

#include <cmath>

#include <algorithm>



using namespace std;



const double eps = 1e-9;



struct node

{

    int val[3];

    bool second;

    double ang[3];

};



char tar[8];

char ori[8];

node A, ans;



int dcmp( double a )

{

    if ( fabs(a) < eps ) return 0;

    return a < 0 ? -1 : 1;

}



int Round( double a )

{

    return (int)(a + 0.5);

}



void init()

{

    scanf( "%s", ori );

    //printf("A: ");

    char tmp[20];

    for ( int i = 0; i < 3; ++i )

    {

        scanf( "%s", tmp );

        sscanf( tmp, "%d", &A.val[i] );

        //printf( "%d ", A.val[i] );

    }

    A.second = false;

    //puts("");

    return;

}



void RGBtoHSL()

{

    double r, g, b;

    if ( A.second )

    {

        r = A.ang[0];

        g = A.ang[1];

        b = A.ang[2];

    }

    else

    {

        r = A.val[0]/255.0;

        g = A.val[1]/255.0;

        b = A.val[2]/255.0;

    }



    double h, l, s;



    //printf( "rgb: %f %f %f
", r, g, b );

    double maxi = max( max(r, g), b );

    double mini = min( min(r, g), b );



    double delta = maxi - mini;

    if ( dcmp( maxi - mini ) == 0 )

    {

        h = 0.0;

    }

    else if ( dcmp( maxi - r ) == 0 )

    {

        if ( dcmp( g - b ) >= 0 )

        {

            h = 60.0*(g-b)/delta+0;

        }

        else

        {

            h = 60.0*(g-b)/delta+360;

        }

    }

    else if ( dcmp( maxi - g ) == 0 )

    {

        h = 60.0*(b-r)/delta+120;

    }

    else if ( dcmp( maxi - b ) == 0 )

    {

        h = 60.0*(r-g)/delta+240;

    }



    l = 0.5*(maxi+mini);

    //printf("l:%f
", l);



    if ( dcmp(l) == 0 || dcmp( delta ) == 0 )

    {

        s = 0.0;

    }

    else if ( dcmp(l) > 0 && dcmp( 0.5 - l ) >= 0 )

    {

        s = delta/(maxi+mini);

    }

    else

    {

        s = delta/(2.0-(maxi+mini));

    }



    //printf( "%s ", tar );

    //printf("%.0f %.0f%% %.0f%%
", h+eps, s*100+eps, l*100+eps );

    //printf("%d %d%% %d%%
", Round(h+eps), Round(s*100+eps), Round(l*100+eps) );

    ans.val[0] = Round(h);

    ans.val[1] = Round(s*100);

    ans.val[2] = Round(l*100);

    return;

}



void RGBtoHSV()

{

    double r, g, b;

    if ( A.second )

    {

        r = A.ang[0];

        g = A.ang[1];

        b = A.ang[2];

    }

    else

    {

        r = A.val[0]/255.0;

        g = A.val[1]/255.0;

        b = A.val[2]/255.0;

    }



    double h, v, s;



    double maxi = max( max(r, g), b );

    double mini = min( min(r, g), b );



    double delta = maxi - mini;

    if ( dcmp( delta ) == 0 )

    {

        h = 0;

    }

    else if ( dcmp( maxi - r ) == 0 )

    {

        if ( dcmp( g - b ) >= 0 )

        {

            h = 60.0*(g-b)/delta+0;

        }

        else

        {

            h = 60.0*(g-b)/delta+360;

        }

    }

    else if ( dcmp( maxi - g ) == 0 )

    {

        h = 60.0*(b-r)/delta+120;

    }

    else if ( dcmp( maxi - b ) == 0 )

    {

        h = 60.0*(r-g)/delta+240;

    }



    if ( dcmp( maxi ) == 0 )

    {

        s = 0;

    }

    else s = (double)(maxi-mini)/maxi;



    v = maxi;



    //printf( "%s ", tar );

    //printf("%f %f %f
", h+eps, s*100+eps, v*100+eps );

    //printf("%d %d%% %d%%
", Round(h+eps), Round(s*100+eps), Round(v*100+eps) );

    ans.val[0] = Round(h);

    ans.val[1] = Round(s*100);

    ans.val[2] = Round(v*100);



    return;

}



void jiuzheng( double &tC )

{

    if ( dcmp( tC ) < 0 ) tC += 1.0;

    if ( dcmp( tC - 1.0 ) > 0 ) tC -= 1.0;

    return;

}



double GetRGB( double p, double q, double tC )

{

    if ( dcmp( 1.0/6.0 - tC ) > 0 )

    {

        return p + ( (q - p) * 6.0 * tC );

    }

    else if ( dcmp( 0.5 - tC ) > 0 )

    {

        return q;

    }

    else if ( dcmp( 2.0/3.0 - tC ) > 0 )

    {

        return p + ( (q-p)*4.0 - (q-p)*6.0*tC );

    }

    else return p;

}



void HSLtoRGB()

{

    double h, s, l;

    double r, g, b;

    //int R, G, B;



    h = A.val[0]/360.0;

    s = A.val[1]/100.0;

    l = A.val[2]/100.0;



    if ( dcmp(s) == 0 )

    {

        r = l;

        g = l;

        b = l;

    }

    else

    {

        double p, q, tR, tG, tB;



        if ( dcmp( 0.5 - l ) > 0 )

            q = l * ( 1.0 + s );

        else q = l + s - ( l * s );



        p = 2 * l - q;



        tR = h + 1.0/3.0;

        tG = h;

        tB = h - 1.0/3.0;



        jiuzheng( tR );

        jiuzheng( tG );

        jiuzheng( tB );



        //r = GetRGB( p, q, tR )*255.0;

        r = GetRGB( p, q, tR );

        //g = GetRGB( p, q, tG )*255.0;

        g = GetRGB( p, q, tG );

        //b = GetRGB( p, q, tB )*255.0;

        b = GetRGB( p, q, tB );

    }



    //printf( "%s ", tar );

    //printf( "RGB: %d %d %d
", r, g, b );

    A.ang[0] = r;

    A.ang[1] = g;

    A.ang[2] = b;

    A.val[0] = Round( r * 255 );

    A.val[1] = Round( g * 255 );

    A.val[2] = Round( b * 255 );

    //printf("HSLtoRGB: %d %d %d
", A.val[0], A.val[1], A.val[2] );

    for ( int i = 0; i < 3; ++i )

        ans.val[i] = A.val[i];



    return;

}



void HSVtoRGB()

{

    double h, s, v;

    int R, G, B;

    double r, g, b;



    h = A.val[0];

    s = A.val[1] / 100.0;

    v = A.val[2] / 100.0;



    if ( dcmp(s) == 0 )

    {

        r = g = b = v;

    }

    else

    {

        int hi = (int)floor(h/60);

        double f = h / 60 - hi;

        double p = v * ( 1 - s );

        double q = v * ( 1 - f*s );

        double t = v * ( 1 - (1-f)*s );



        switch( hi )

        {

            case 0: r = v, g = t, b = p; break;

            case 1: r = q, g = v, b = p; break;

            case 2: r = p, g = v, b = t; break;

            case 3: r = p, g = q, b = v; break;

            case 4: r = t, g = p, b = v; break;

            case 5: r = v, g = p, b = q; break;

        }

    }



    R = Round( r * 255.0 );

    G = Round( g * 255.0 );

    B = Round( b * 255.0 );



    //printf( "%s ", tar );

    //printf( "%d %d %d
", R, G, B );

    A.ang[0] = r;

    A.ang[1] = g;

    A.ang[2] = b;



    A.val[0] = R;

    A.val[1] = G;

    A.val[2] = B;

    for ( int i = 0; i < 3; ++i )

        ans.val[i] = A.val[i];

    return;

}



void HSVtoHSL()

{

    HSVtoRGB();

    A.second = true;

    RGBtoHSL();

    return;

}



void HSLtoHSV()

{

    HSLtoRGB();

    A.second = true;

    RGBtoHSV();

    return;

}



int main()

{

    while ( scanf( "%s", tar ) == 1 )

    {

        init();

        if ( ori[0] == 'R' )

        {

            if ( tar[2] == 'L' ) RGBtoHSL();

            else if ( tar[0] == 'R' )

            {

                for ( int i = 0; i < 3; ++i )

                    ans.val[i] = A.val[i];

            }

            else RGBtoHSV();

        }

        else if ( ori[2] == 'L' )

        {

            if ( tar[0] == 'R' ) HSLtoRGB();

            else if ( tar[2] == 'L' )

            {

                for ( int i = 0; i < 3; ++i )

                    ans.val[i] = A.val[i];

            }

            else HSLtoHSV();

        }

        else

        {

            if ( tar[0] == 'R' ) HSVtoRGB();

            else if ( tar[2] == 'V' )

            {

                for ( int i = 0; i < 3; ++i )

                    ans.val[i] = A.val[i];

            }

            else HSVtoHSL();

        }



        printf( "%s ", tar );

        if ( tar[0] == 'R' )

        {

            printf( "%d %d %d
", ans.val[0], ans.val[1], ans.val[2] );

        }

        else printf( "%d %d%% %d%%
", ans.val[0], ans.val[1], ans.val[2] );

    }

    return 0;

}