#include using namespace std; //#define int long long //TEMPLATE START---------------8<---------------8<---------------8<---------------8<---------------// typedef long long ll; typedef long double ld; typedef pair pii; typedef pair pll; typedef vector vi; typedef vector vl; typedef vector vst; typedef vector vb; typedef vector vld; typedef vector vpii; typedef vector vpll; typedef vector > vvi; const int INF = (0x7FFFFFFFL); const ll INFF = (0x7FFFFFFFFFFFFFFFL); const string ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; const int MOD = 1e9 + 7; const int MODD = 998244353; const string alphabet = "abcdefghijklmnopqrstuvwxyz"; const double PI = acos(-1.0); const double EPS = 1e-9; const string Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; int dx[9] = { 1, 0, -1, 0, 1, -1, -1, 1, 0 }; int dy[9] = { 0, 1, 0, -1, -1, -1, 1, 1, 0 }; #define ln '\n' #define scnaf scanf #define sacnf scanf #define sancf scanf #define SS(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__); template void MACRO_VAR_Scan(T& t){cin >> t;}template void MACRO_VAR_Scan(First& first, Rest&...rest){cin >> first;MACRO_VAR_Scan(rest...);} #define SV(type,c,n) vector c(n);for(auto& i:c)cin >> i; #define SVV(type,c,n,m) vector> c(n,vector(m));for(auto& r:c)for(auto& i:r)cin >> i; templateostream &operator<<(ostream &o,const pair&j){o<<"{"<ostream &operator<<(ostream &o,const map&j){o<<"{";for(auto t=j.begin();t!=j.end();++t)o<<(t!=j.begin()?", ":"")<<*t;o<<"}";return o;} templateostream &operator<<(ostream &o,const set&j){o<<"{";for(auto t=j.begin();t!=j.end();++t)o<<(t!=j.begin()?", ":"")<<*t;o<<"}";return o;} templateostream &operator<<(ostream &o,const multiset&j){o<<"{";for(auto t=j.begin();t!=j.end();++t)o<<(t!=j.begin()?", ":"")<<*t;o<<"}";return o;} templateostream &operator<<(ostream &o,const vector&j){o<<"{";for(int i=0;i<(int)j.size();++i)o<<(i>0?", ":"")< int print(Head&& head){cout << head;print();return 0;} template int print(Head&& head,Tail&&... tail){cout<(tail)...);return 0;} #ifdef LOCAL inline int dump(void){cerr << endl; return 0;} template int dump(Head&& head){cerr << head;dump();return 0;} template int dump(Head&& head,Tail&&... tail){cerr<(tail)...);return 0;} #define debug(...) do{cerr<<__LINE__<<": "<<#__VA_ARGS__<<" = ";dump(__VA_ARGS__);}while(0) #define ER(x) cerr << #x << " = " << (x) << endl; #define ERV(v) {cerr << #v << " : ";for(const auto& xxx : v){cerr << xxx << " ";}cerr << "\n";} #else #define dump(...) #define debug(...) #define ER(x) #define ERV(v) #endif template void PA(T &a){int ASIZE=sizeof(a)/sizeof(a[0]);for(int ii=0;ii void PV(T &v){int VSIZE=v.size();for(int ii=0;ii void sankou(bool x,A a,B b){cout<<((x)?(a):(b))<=ll(b);--i) #define RREP(...) _overload3(__VA_ARGS__,RREPI,_RREP,)(__VA_ARGS__) #define EACH(e,v) for(auto& e : v) #define PERM(v) sort((v).begin(),(v).end());for(bool c##p=1;c##p;c##p=next_permutation((v).begin(),(v).end())) #define ADD(a,b) a=(a+ll(b))%MOD #define MUL(a,b) a=(a*ll(b))%MOD inline ll MOP(ll x,ll n,ll m=MOD){ll r=1;while(n>0){if(n&1)(r*=x)%=m;(x*=x)%=m;n>>=1;}return r;} inline ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}inline ll lcm(ll a,ll b){return a*b/gcd(a,b);}inline ll POW(ll a,ll b){ll c=1ll;do{if(b&1)c*=1ll*a;a*=1ll*a;}while(b>>=1);return c;} template inline bool between(T x,A a,B b) {return ((a<=x)&&(x inline T sqr(T x){return x*x;} template inline bool chmax(A &a,const B &b){if(a inline bool chmin(A &a,const B &b){if(a>b){a=b;return 1;}return 0;} #define tmax(x,y,z) max((x),max((y),(z))) #define tmin(x,y,z) min((x),min((y),(z))) #define PB emplace_back #define MP make_pair #define MT make_tuple #define all(v) (v).begin(),(v).end() #define rall(v) (v).rbegin(),(v).rend() #define SORT(v) sort((v).begin(),(v).end()) #define RSORT(v) sort((v).rbegin(),(v).rend()) #define EXIST(s,e) (find((s).begin(),(s).end(),(e))!=(s).end()) #define EXISTST(s,c) (((s).find(c))!=string::npos) #define POSL(x,val) (lower_bound(x.begin(),x.end(),val)-x.begin()) #define POSU(x,val) (upper_bound(x.begin(),x.end(),val)-x.begin()) #define GEQ(x,val) (int)(x).size() - POSL((x),(val)) #define GREATER(x,val) (int)(x).size() - POSU((x),(val)) #define LEQ(x,val) POSU((x),(val)) #define LESS(x,val) POSL((x),(val)) #define SZV(a) int((a).size()) #define SZA(a) sizeof(a)/sizeof(a[0]) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) #define MEMINF(a) memset(a,0x3f,sizeof(a)) #define FILL(a,b) memset(a,b,sizeof(a)) #define UNIQUE(v) sort((v).begin(),(v).end());(v).erase(unique((v).begin(),(v).end()),(v).end()) struct abracadabra{ abracadabra(){ cin.tie(0); ios::sync_with_stdio(0); cout << fixed << setprecision(20); cerr << fixed << setprecision(5); }; } ABRACADABRA; //TEMPLATE END---------------8<---------------8<---------------8<---------------8<---------------// template struct Edge { int from, to; T weight; Edge() : from(0), to(0), weight(0) {} Edge(int f, int t, T w) : from(f), to(t), weight(w) {} }; template using Edges = vector< Edge< T > >; template using Graph = vector< Edges< T > >; template void add_edge(Graph< T > &g, int from, int to, T w = 1) { g[from].emplace_back(from, to, w); g[to].emplace_back(to, from, w); } template void add_arc(Graph< T > &g, int from, int to, T w = 1) { g[from].emplace_back(from, to, w); } template void add_to_edges(Edges< T > &e, int from, int to, T w = 1) { e.emplace_back(from, to, w); } /* ・グラフ用テンプレート > Dijkstra > BellmanFord > WarshallFloyd > Kruskal [応用] 単一終点最短路問題は, すべての有向辺を逆向きに張り替えると, 単一始点最短路問題に帰着できる. [使用例] Graph g(V); // 頂点数V, 重さの型がintのグラフを宣言 add_edge(g, a, b, c); // グラフgに, 始点a, 終点b, 重さcの無向辺を追加 add_arc(g, a, b, c); // グラフgに, 始点a, 終点b, 重さcの有向辺を追加 add_to_edges(edges, a, b, c); // 辺集合edgesに, 始点a, 終点b, 重さcの辺を追加 */ template vector< T > Dijkstra(Graph< T > &g, int from) { const auto INF = numeric_limits< T >::max() / 10; vector< T > dist(g.size(), INF); dist[from] = 0; using P = pair< T, int >; priority_queue< P, vector< P >, greater< P > > que; que.emplace(dist[from], from); while (not que.empty()) { T weight; int idx; tie(weight, idx) = que.top(); que.pop(); if (dist[idx] < weight) continue; for (auto &e : g[idx]) { auto next_weight = weight + e.weight; if (dist[e.to] <= next_weight) continue; dist[e.to] = next_weight; que.emplace(dist[e.to], e.to); } } return dist; } /* ・ダイクストラ法 > O(ElogV) [E:辺の数, V:頂点の数] [備考] 負辺の存在しないグラフに対する単一始点全点間最短路を求めるアルゴリズム [注意] 結果を足し合わせる際, INFの大きさに注意 [使用例] auto dij = Dijkstra(g, s); // グラフgにおける, 始点sからの最短路 */ bool board[2020][2020]; signed main() { SS(int, H, W); SV(string, board_st, H); REP(i, H) REP(j, W) board[i][j] = (board_st[i][j] == 'k'); // vst board(H, string(W, '.')); Graph g(H * W); auto f = [&](int h, int w) -> int { return h * W + w; }; auto in = [&](int h, int w) -> bool { return h >= 0 and h < H and w >= 0 and w < W; }; // ll cnt = 0; REP(i, H) REP(j, W) { REP(k, 2) { int ni = i + dx[k]; int nj = j + dy[k]; if (not in(ni, nj)) continue; if (board[ni][nj]) { // if (board[ni][nj] == 'k') { add_arc(g, f(i, j), f(ni, nj), 1 + (ni + nj)); } else { add_arc(g, f(i, j), f(ni, nj), 1); } // ++cnt; } } // debug(cnt); auto dij = Dijkstra(g, f(0, 0)); print(dij[f(H - 1, W - 1)]); }