#include #include #include #include #include #include #include #include #include #include #include #include #include #include #define _overload3(_1,_2,_3,name,...) name #define _rep(i,n) repi(i,0,n) #define repi(i,a,b) for(ll i=ll(a);ibool chmax(T &a, const T &b) { if (abool chmin(T &a, const T &b) { if (b void cins(itr first,itr last){ for (auto i = first;i != last;i++){ cin >> (*i); } } template void array_output(itr start,itr goal){ string ans = "",k = " "; for (auto i = start;i != goal;i++) ans += to_string(*i)+k; if (!ans.empty()) ans.pop_back(); PRINT(ans); } ll gcd(ll a, ll b) { return a ? gcd(b%a,a) : b; } const ll INF = 1e17; const ll MOD = 1000000007; typedef pair P; const ll MAX = 1005; constexpr ll nx[4] = {1,0,-1,0}; constexpr ll ny[4] = {0,1,0,-1}; int main(){ cin.tie(0); ios::sync_with_stdio(false); ll r,c; cin >> r >> c; ll sx,sy,gx,gy; cin >> sy >> sx >> gy >> gx; vector grid(r); vector> ans(r,vector(c,INF)); vector> done(r,vector(c,0)); rep(i,r) cin >> grid[i]; queue

q; ans[sx-1][sy-1] = 0; q.push(P(sx-1,sy-1)); while(!q.empty()){ ll x,y; tie(x,y) = q.front(); done[x][y] = 1; q.pop(); rep(i,4){ ll xn = x+nx[i],yn = y+ny[i]; if (xn >= 0 && xn < r && yn >= 0 && yn < c && grid[xn][yn] == '.' && done[xn][yn] == 0){ chmin(ans[xn][yn],ans[x][y]+1); q.push(P(xn,yn)); } } } PRINT(ans[gx-1][gy-1]); }