[Topcoder] SRM207

Div2 Lev3

 

#include <iostream> #include <cstring> #include <vector> #include <queue> #include <deque> using namespace std; typedef struct node { string pos; int hasKillRook; int hasKillQueen; int step; } node; const int coffset[8] = {-2, -2, 2, 2, -1, 1, -1, 1}; const int roffset[8] = {-1, 1, -1, 1, -2, -2, 2, 2}; class CaptureThemAll { private: public: int fastKnight(string knight, string rook, string queen) { int visited[4][64] = {0}; deque<node> q; // push the first pos of knight node n; n.pos = knight; n.hasKillRook = 0; n.hasKillQueen = 0; n.step = 0; visited[0][64] = 1; q.push_back(n); while (!q.empty()) { n = q.front(); q.pop_front(); cerr << n.pos << endl; if (n.hasKillQueen && n.hasKillRook) return n.step; else if (n.hasKillQueen) visited[2][(n.pos[0] - 'a') * 8 + n.pos[1] - '1']++; else if (n.hasKillRook) visited[1][(n.pos[0] - 'a') * 8 + n.pos[1] - '1']++; else visited[0][(n.pos[0] - 'a') * 8 + n.pos[1] - '1']++; for (int i = 0; i < 8; i++) { string curp(2, '/0'); curp[0] = n.pos[0] + coffset[i]; curp[1] = n.pos[1] + roffset[i]; // out of bound if (curp[0] < 'a' || curp[0] > 'h' || curp[1] < '1' || curp[1] > '8') continue; node newn = n; newn.pos = curp; if (curp == queen) newn.hasKillQueen = 1; if (curp == rook) newn.hasKillRook = 1; newn.step++; int flg = 0; if (newn.hasKillQueen && newn.hasKillRook) return newn.step; else if (newn.hasKillQueen) flg = 2; else if (newn.hasKillRook) flg = 1; else flg = 0; if (visited[flg][(newn.pos[0] - 'a') * 8 + newn.pos[1] - '1']) continue; q.push_back(newn); } } return -1; } }; int main() { CaptureThemAll cta; cout << "example 0: " << cta.fastKnight("a1", "b3", "c5") << endl; cout << "example 1: " << cta.fastKnight("b1", "c3", "a3") << endl; cout << "example 2: " << cta.fastKnight("a1", "a2", "b2") << endl; cout << "example 3: " << cta.fastKnight("a5", "b7", "e4") << endl; cout << "example 4: " << cta.fastKnight("h8", "e2", "d2") << endl; return 0; }