Topcoder Inv 2001 Semi A+B 1000 pointer

ChessCover.cpp

#include <bits/stdc++.h>

#define mp make_pair
#define vstr vector<string>
#define pb push_back
#define all(x) begin(x), end(x)

#define sz(x) int(x.size())
#define P(X) cout << X << "\t"
#define NL cout << endl
#define FOR(I,N) for(int I = 0; I < N; ++I)

using namespace std;

typedef pair<int, int> Coord;
typedef pair<int, int> Incr;
static constexpr Incr UP = mp(-1, 0), DN = mp(1, 0), LT = mp(0, -1), RT = mp(0, 1);
static constexpr Incr NE = mp(-1, 1), NW = mp(-1, -1), SE = mp(1, 1), SW = mp(1, -1);

template<typename T> struct Iter2d
{
// ... snip (See iter2d.cpp) ...
};

struct ChessCover
{
    typedef Iter2d<char> Iter;
    
    void attack(vector<vector<char>> &board, const Coord &c, const std::initializer_list<Incr> dirs)
    {
        for(const auto &dir:dirs) 
            for(Iter it = Iter(board, c, dir).next(), ite = it.end(); it != ite && (*it == 'U' || *it == '*'); ++it) 
                *it = '*';
    }
    
    void attackOne(vector<vector<char>> &board, const Coord &c, std::initializer_list<Incr> dirs)
    {
        for(const auto &dir:dirs) 
        {
            Iter it(board, c, dir);
            if(++it && *it == 'U') *it = '*';
        }
    }
    
    int getSafe(vector<string> param0)
    {
        vector<vector<char>> board;
        FOR(i, param0.size()) board.push_back(vector<char>(all(param0[i])));
        
        FOR(i, sz(board))
        FOR(j, sz(board[0]))
        {
            Coord c = mp(i, j);
            switch(board[i][j])
            {
                case 'Q': attack(board, c, {UP, DN, LT, RT, NE, NW, SE, SW}); break;
                case 'R': attack(board, c, {UP, DN, LT, RT}); break;
                case 'B': attack(board, c, {NE, NW, SE, SW}); break;
                case 'P': attackOne(board, c, {NE, NW, SE, SW}); break;
                case 'K': 
                    attackOne(board, c, {mp(-2, -1), mp(-1, -2), mp(-2, 1), mp(-1, 2),  
                        mp(2, -1), mp(1, -2), mp(2, 1), mp(1, 2)}); 
                break;
            }
        }
        
        int cnt = 0;
        FOR(i, sz(board))
        {
            cnt += count(all(board[i]), 'U');
        }
        
        return cnt;
    }
};