#include <bits/stdc++.h> #define fst first #define snd second #define pb push_back #define SZ(x) (int)x.size() #define ALL(x) x.begin(),x.end() #define forn(i,a,b) for(int i = a; i<b; i++) #define mset(a,v) memset(a,v,sizeof(a)) #define FIN ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); using namespace std; typedef long long ll; string o = "RGW"; int main(){ ll n,m; cin>>n>>m; vector<string> s(n); forn(i,0,n) cin>>s[i]; //cout<<"precalculos listos\n"; ll res = 0; while(true){ vector<pair<ll,ll>> ver; vector<pair<ll,ll>> hor; forn(i,0,n){ forn(j,0,m){ bool vert = true; bool hori = true; forn(h,0,3){ if(i+h>=n || s[i+h][j]!=o[h]) vert=false; if(j+h>=m || s[i][j+h]!=o[h]) hori=false; } if(vert) ver.pb({i,j}) ;//, cout<<"vert "<<i<<" "<<j<<'\n'; if(hori) hor.pb({i,j}) ;//, cout<<"hori "<<i<<" "<<j<<'\n'; } } vector<pair<ll,pair<ll,ll>>> opc; pair<ll,pair<ll,ll>> best = {100000,{1000,1000}}; forn(i,0,SZ(ver)){ ll cnt = 0; ll j1=lower_bound(ALL(hor),ver[i])-hor.begin(); if(j1!=SZ(hor) && hor[j1]==ver[i]) cnt++; ll j2=lower_bound(ALL(hor),pair<ll,ll>{ver[i].fst+1,ver[i].snd-1}) - hor.begin(); if(j2!=SZ(hor) && hor[j2]==pair<ll,ll>{ver[i].fst+1,ver[i].snd-1}) cnt++; ll j3=lower_bound(ALL(hor),pair<ll,ll>{ver[i].fst+2,ver[i].snd-2}) - hor.begin(); if(j3!=SZ(hor) && hor[j3]==pair<ll,ll>{ver[i].fst+2,ver[i].snd-2}) cnt++; opc.pb({cnt,{0,i}}); best=min(best,{cnt,{0,i}}); } //cout<<"intersecciones verticales listas\n"; forn(i,0,SZ(hor)){ ll cnt = 0; ll j1=lower_bound(ALL(ver),hor[i])-ver.begin(); if(j1!=SZ(ver) && ver[j1]==hor[i]) cnt++; ll j2=lower_bound(ALL(ver),pair<ll,ll>{hor[i].fst-1,hor[i].snd+1}) - ver.begin(); if(j2!=SZ(ver) && ver[j2]==pair<ll,ll>{hor[i].fst-1,hor[i].snd+1}) cnt++; ll j3=lower_bound(ALL(ver),pair<ll,ll>{hor[i].fst-2,hor[i].snd+2}) - ver.begin(); if(j3!=SZ(ver) && ver[j3]==pair<ll,ll>{hor[i].fst-2,hor[i].snd+2}) cnt++; opc.pb({cnt,{0,i}}); best=min(best,{cnt,{1,i}}); } //cout<<"intersecciones horizontales listas\n"; //cout<<best.fst<<" "<<best.snd.fst<<" "<<best.snd.snd<<'\n'; if(best.fst!=100000){ res++; if(best.snd.fst==0){ forn(h,0,3){ s[ver[best.snd.snd].fst+h][ver[best.snd.snd].snd]='-'; } ver.erase(ver.begin()+best.snd.snd); }else{ forn(h,0,3){ s[hor[best.snd.snd].fst][hor[best.snd.snd].snd+h]='-'; } hor.erase(hor.begin()+best.snd.snd); } }else{ break; } } cout<<res<<'\n'; return 0; }