#include <bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<int , int> pi; typedef pair<ll , ll> pll; typedef vector<int> vi; typedef vector<bool> vb; typedef vector<ll> vll; typedef vector<vi> vvi; typedef vector<vll> vvll; #define pb push_back #define lb lower_bound #define up upper_bound #define F first #define S second #define nd "\n" #define forad(i , a , b) for(int i = a; i < (int) b; i++) #define forat(i , a , b) for(int i = a; i >= b; i--) #define debug(x) cout << #x << " = " << x << nd #define debugv(x , s) cout << #x << " = " << forad(i , 0 , s) cout << x[i] << " "; cout << nd #define faster ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0) #define all(x) x.begin() , x.end() const ll mod = 1e9+7 , INF = 1e9; ll inv(ll x){return x <= 1 ? x : (mod - mod/x) * inv(mod%x) % mod;} #define smod(a , b) (a%mod+b%mod)%mod #define rmod(a , b) (a%mod - b%mod + mod)%mod #define mmod(a , b) (a%mod) * (b%mod)%mod #define dmod(a , b) (a%mod) * inv(b) %mod int n, s; vector<string> a; queue<pi> cola; vvi dist; void moverse(int fromi, int fromj, int toi, int toj) { if (dist[fromi][fromj] + 1 < dist[toi][toj]) { cola.push({toi, toj}); dist[toi][toj] = dist[fromi][fromj] + 1; } } void ffm() { int k = cola.size(); while (k--) { pi front = cola.front(); cola.pop(); int i = front.first , j = front.second; if (i > 0) moverse(i, j, i-1, j); if (j > 0) moverse(i, j, i, j-1); if (i < n-1) moverse(i, j, i+1, j); if (j < n-1) moverse(i, j, i, j+1); } } bool cumple(int x,int y){return a[x][y]=='G' || a[x][y]=='M';} bool puedo(int mt,int bt){return mt/s < bt;} void ir(int acx,int acy,int irx,int iry, vvi bt, int w){ if(!cumple(acx , acy)) return; if(bt >= dist[actx][acty]) return; int aux = bt[actx][acty] - w; if(puedo(bt , aux)){ dist[acx][acy] = bt; cola.push({acx , acy}); } } vvi bees(vector<pi> h){ dist.assign(n, vi(n, INF)); while(!cola.empty()) cola.pop(); for(auto x : h){ dist[x.F][x.S] = 0; cola.push(x); } while(!cola.empty()) ffm(); return dist; } bool mecho_ff(int acx,int acy,int irx,int iry, vvi bt, int w){ dist.assign(n, vi(n, INF)); while(!cola.empty()) cola.pop(); if(bt[acx][acy] <= w) return false; dist[acx][acy] = 0; cola.push({acx,acy}); while(!cola.empty()){ int k = cola.size(); while(k--){ auto[x,y] = cola.front(); cola.pop(); int nt = dist[x][y] + 1; if(x>0) ir(x-1,y); if(y>0) ir(x,y-1); if(x<n-1) ir(x+1,y); if(y<n-1) ir(x,y+1); } } int dx[4]={-1,0,1,0}, dy[4]={0,-1,0,1}; forad(i,0,4){ int nx=irx+dx[i], ny=iry+dy[i]; if(nx<0||ny<0||nx>=n||ny>=n) continue; if(!cumple(nx,ny)) continue; if(dist[nx][ny]==INF) continue; if(puedo(dist[nx][ny], bt[nx][ny]-w)) return true; } return false; } int main(){ faster; cin >> n >> s; a.resize(n); forad(i,0,n) cin >> a[i]; int acx , acy , irx , iry; vector<pi> h; forad(i,0,n){ forad(j,0,n){ if(a[i][j]=='M') acx=i,acy=j; else if(a[i][j]=='H') h.pb({i,j}); else if(a[i][j]=='D') irx=i,iry=j; } } auto bt = bees(h); int l = 0, r = n*n, m; while(l<=r){ m = l + (r-l)/2; if(mecho_ff(acx,acy,irx,iry,bt,mid)) l = m+1; else r = mid-1; } cout << l << nd; }

mecho.cpp: In function 'void ir(int, int, int, int, vvi, int)':
mecho.cpp:68:19: error: 'actx' was not declared in this scope; did you mean 'acx'?
   68 |     if(bt >= dist[actx][acty]) return;
      |                   ^~~~
      |                   acx
mecho.cpp:68:25: error: 'acty' was not declared in this scope; did you mean 'acy'?
   68 |     if(bt >= dist[actx][acty]) return;
      |                         ^~~~
      |                         acy
mecho.cpp:69:18: error: 'actx' was not declared in this scope; did you mean 'acx'?
   69 |     int aux = bt[actx][acty] - w;
      |                  ^~~~
      |                  acx
mecho.cpp:69:24: error: 'acty' was not declared in this scope; did you mean 'acy'?
   69 |     int aux = bt[actx][acty] - w;
      |                        ^~~~
      |                        acy
mecho.cpp:70:14: error: cannot convert 'vvi' {aka 'std::vector<std::vector<int> >'} to 'int'
   70 |     if(puedo(bt , aux)){
      |              ^~
      |              |
      |              vvi {aka std::vector<std::vector<int> >}
mecho.cpp:64:16: note:   initializing argument 1 of 'bool puedo(int, int)'
   64 | bool puedo(int mt,int bt){return mt/s < bt;}
      |            ~~~~^~
mecho.cpp:71:26: error: cannot convert 'vvi' {aka 'std::vector<std::vector<int> >'} to '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} in assignment
   71 |         dist[acx][acy] = bt;
      |                          ^~
      |                          |
      |                          vvi {aka std::vector<std::vector<int> >}
mecho.cpp: In function 'bool mecho_ff(int, int, int, int, vvi, int)':
mecho.cpp:97:23: error: too few arguments to function 'void ir(int, int, int, int, vvi, int)'
   97 |             if(x>0) ir(x-1,y);
      |                     ~~^~~~~~~
mecho.cpp:66:6: note: declared here
   66 | void ir(int acx,int acy,int irx,int iry, vvi bt, int w){
      |      ^~
mecho.cpp:98:23: error: too few arguments to function 'void ir(int, int, int, int, vvi, int)'
   98 |             if(y>0) ir(x,y-1);
      |                     ~~^~~~~~~
mecho.cpp:66:6: note: declared here
   66 | void ir(int acx,int acy,int irx,int iry, vvi bt, int w){
      |      ^~
mecho.cpp:99:25: error: too few arguments to function 'void ir(int, int, int, int, vvi, int)'
   99 |             if(x<n-1) ir(x+1,y);
      |                       ~~^~~~~~~
mecho.cpp:66:6: note: declared here
   66 | void ir(int acx,int acy,int irx,int iry, vvi bt, int w){
      |      ^~
mecho.cpp:100:25: error: too few arguments to function 'void ir(int, int, int, int, vvi, int)'
  100 |             if(y<n-1) ir(x,y+1);
      |                       ~~^~~~~~~
mecho.cpp:66:6: note: declared here
   66 | void ir(int acx,int acy,int irx,int iry, vvi bt, int w){
      |      ^~
mecho.cpp: In function 'int main()':
mecho.cpp:132:40: error: 'mid' was not declared in this scope; did you mean 'mod'?
  132 |         if(mecho_ff(acx,acy,irx,iry,bt,mid)) l = m+1;
      |                                        ^~~
      |                                        mod