/* -*- coding: utf-8 -*- * * 240.cc: No.240 ナイト散歩 - yukicoder */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; /* constant */ const int N = 3; const int CX = 2 * N, CY = 2 * N; const int dxs[8] = {2, 1, -1, -2, -2, -1, 1, 2}; const int dys[8] = {-1, -2, -2, -1, 1, 2, 2, 1}; /* typedef */ struct Stat { int d, x, y; Stat() {}; Stat(int _d, int _x, int _y): d(_d), x(_x), y(_y) {} }; /* global variables */ bool used[CY * 2 + 1][CX * 2 + 1]; /* subroutines */ /* main */ int main() { int gx, gy; cin >> gx >> gy; gx += CX, gy += CY; queue q; q.push(Stat(0, CX, CY)); bool ok = false; while (! q.empty()) { Stat u = q.front(); q.pop(); if (u.x == gx && u.y == gy) { ok = true; break; } if (u.d >= N) continue; for (int di = 0; di < 8; di++) { int vx = u.x + dxs[di], vy = u.y + dys[di]; if (! used[vy][vx]) { used[vy][vx] = true; q.push(Stat(u.d + 1, vx, vy)); } } } cout << (ok ? "YES" : "NO") << endl; return 0; }