king_to_corner.cpp

#include <cstdio>

using namespace std;

int t[8][8] =
{
    {9, 9, 9, 9, 5, 6, 7, 8},
    {8, 8, 4, 3, 1, 1, 1, 1},
    {7, 7, 5, 2, 1, 1, 1, 1},
    {1, 6, 6, 1, 1, 1, 1, 1},
    {1, 4, 5, 1, 5, 1, 1, 1},
    {1, 3, 1, 4, 1, 4, 1, 1},
    {1, 2, 3, 1, 1, 1, 3, 1},
    {1, 1, 1, 2, 1, 1, 1, 1}
};

int result[64];

int distance(int from_x, int from_y, int to_x, int to_y)
{
    return (to_x-from_x)*(to_x-from_x)+(to_y-from_y)*(to_y-from_y);
}

int move_x(int move, int x)
{
    int dx[] = {0,1,1,1,0,-1,-1,-1};
    return x + dx[move];
}

int move_y(int move, int y)
{
    int dy[] = {1,1,0,-1,-1,-1,0,1};
    return y + dy[move];
}

bool inBoard(int move, int x, int y)
{
    return (move_x(move,x) >= 0 && move_x(move,x) < 8 && move_y(move,y) >= 0 && move_y(move,y) < 8);
}

bool moveSpelniaWarunkiZadania(int move, int x, int y, int to_x, int to_y)
{
    if(!inBoard(move,x,y)) { return false; }
    if(distance(x,y,to_x, to_y) < distance(move_x(move,x), move_y(move,y),to_x,to_y)) { return false; }
    
    int lastDigitOfCurrent;
    int firstDigitOfTarget;
    
    lastDigitOfCurrent = t[x][y]%10;
    
    firstDigitOfTarget = t[move_x(move,x)][move_y(move,y)];
    while(firstDigitOfTarget/10 > 0)
    {
        firstDigitOfTarget /= 10;
    }
    
    return (lastDigitOfCurrent < firstDigitOfTarget);
}

bool ruszSie(int x, int y, int to_x, int to_y, int pos_to_save)
{
    if(x == to_x && y == to_y) { return true; } // TEGO NIE NAPISAŁEM NA KARTKÓWCE. TYLKO.
    for(int i = 0; i<8; i++)
    {
        if(moveSpelniaWarunkiZadania(i, x, y, to_x, to_y))
        {
            if(ruszSie(move_x(i,x), move_y(i,y), to_x, to_y,pos_to_save+1))
            {
                result[pos_to_save] = i;
                printf("ending on (%d, %d) trying to get to (%d, %d)\n",x,y,to_x,to_y);
                return true;
            }
        }
    }
    return false;
}

int czySieDa(int w, int k)
{
    if(ruszSie(w, k, 0, 0, 0))
    {
        return 0;
    }
    if(ruszSie(w, k, 0, 7, 0))
    {
        return 1;
    }
    if(ruszSie(w, k, 7, 0, 0))
    {
        return 2;
    }
    if(ruszSie(w, k, 7, 7, 0))
    {
        return 3;
    }
    return -1;
}

int main()
{
    printf("%d\n",czySieDa(6,2));
    for(int i = 0; i<10; i++)
    {
        printf("%d ",result[i]);
    }
    printf("\n");
    return 0;
}