解説

cpp17

#include <bits/stdc++.h>
using namespace std;
using ll =long long;

ll dango1(ll x,ll y){
  return x*1000000+y;
}
int main() { 
   ll h,w;cin >> h >> w;
  vector<vector<vector<char>>> s(6,vector<vector<char>>(h,vector<char>(w)));
  vector<vector<vector<bool>>> t(6,vector<vector<bool>>(h,vector<bool>(w,1)));
  vector<vector<vector<int>>> u(6,vector<vector<int>>(h,vector<int>(w,100000000)));
  string a;
  a="CLDZRG";
  ll p;//スタート地点
  for(int i=0;i<h;i++){
    for(int j=0;j<w;j++){
      cin >> s[0][i][j];
      if(s[0][i][j]=='S'){
        p=dango1(i,j);
        u[0][i][j]=0;
      }
      if(s[0][i][j]=='#')t[0][i][j]=0;
      for(int k=1;k<6;k++){
         t[k][i][j]=t[0][i][j];
      }
    }
  }
  queue<pair<ll,ll>> q;
  q.push({p,0});
  ll ans=0;
  while(!q.empty()){
    ll b=q.front().first,c=q.front().second;
    ll d=b/1000000,e=b%1000000;

    q.pop();
    if(!t[c][d][e])continue;
    t[c][d][e]=0;
    if(c==5&&s[c][d][e]=='G'){
       cout << u[c][d][e];
      return 0;
    }
    if(s[c][d][e]==a[c]){
      u[c+1][d][e]=min(u[c][d][e],u[c+1][d][e]);
      q.push({dango1(d,e),c+1});
      continue;
    }

    if(d!=0 && t[c][d-1][e]){
       q.push({dango1(d-1,e),c});
      u[c][d-1][e]=min(u[c][d-1][e],u[c][d][e]+1);
    }
    if(d!=h-1 && t[c][d+1][e]){
      q.push({dango1(d+1,e),c});
      u[c][d+1][e]=min(u[c][d+1][e],u[c][d][e]+1);
    }
    if(e!=0 && t[c][d][e-1]){
      q.push({dango1(d,e-1),c});
      u[c][d][e-1]=min(u[c][d][e-1],u[c][d][e]+1);
    }
    if(e!=w-1 && t[c][d][e+1]){
      q.push({dango1(d,e+1),c});
      u[c][d][e+1]=min(u[c][d][e+1],u[c][d][e]+1);
    }
  }
  cout << -1;
}