#include <bits/stdc++.h>
using namespace std;
#define ti tuple<int,int,int,bool>
const int N = 3010;
int m,n,ans;
char c[N][N];
bool v[N][N],h[N][N];
int cv[N][N],ch[N][N];
set<ti> s;
void del(ti a,ti tt)
{
auto &[c,x,y,t] = a;
if(t==0)
{
auto it = s.find({ch[x-2][y+2],x-2,y+2,1});
if(it!=s.end() and *it!=tt) ch[x-2][y+2]--,s.erase(it),ans++;
else if(x>2 and y+2<=n and ch[x-2][y+2])
{
ch[x-2][y+2]--;
if(ch[x-2][y+2]==1) s.insert({ch[x-2][y+2],x-2,y+2,1});
}
it = s.find({ch[x-1][y+1],x-1,y+1,1});
if(it!=s.end() and *it!=tt) ch[x-1][y+1]--,s.erase(it),ans++;
else if(x>1 and y+1<=n and ch[x-1][y+1]
{
ch[x-1][y+1]--;
if(ch[x-1][y+1]==1) s.insert({ch[x-1][y+1],x-1,y+1,1});
}
it = s.find({ch[x][y],x,y,1});
if(it!=s.end() and *it!=tt) ch[x][y]--,s.erase(it),ans++;
else if(ch[x][y])
{
ch[x][y]--;
if(ch[x][y]==1) s.insert({ch[x][y],x,y,1});
}
cv[x][y] = 0;
}
else
{
auto it = s.find({cv[x+2][y-2],x+2,y-2,0});
if(it!=s.end() and *it!=tt) cv[x+2][y-2]--,s.erase(it),ans++;
else if(x+2<=m and y>2 and cv[x+2][y-2])
{
cv[x+2][y-2]--;
if(cv[x+2][y-2]==1) s.insert({cv[x+2][y-2],x+2,y-2,0});
}
it = s.find({cv[x+1][y-1],x+1,y-1,0});
if(it!=s.end() and *it!=tt) cv[x+1][y-1]--,s.erase(it),ans++;
else if(x+1<=m and y>1 and cv[x+1][y-1])
{
cv[x+1][y-1]--;
if(cv[x+1][y-1]==1) s.insert({cv[x+1][y-1],x+1,y-1,0});
}
it = s.find({cv[x][y],x,y,0});
if(it!=s.end() and *it!=tt) cv[x][y]--,s.erase(it),ans++;
else if(cv[x][y])
{
cv[x][y]--;
if(cv[x][y]==1) s.insert({cv[x][y],x,y,0});
}
ch[x][y] = 0;
}
s.erase({c,x,y,t});
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> m >> n;
for(int i = 1;i <= m;i++) for(int j = 1;j <= n;j++) cin >> c[i][j];
for(int i = 1;i <= m;i++) for(int j = 1;j <= n;j++)
{
if(i>2 and c[i-2][j]=='R' and c[i-1][j]=='G' and c[i][j]=='W') v[i][j] = 1;
if(j>2 and c[i][j-2]=='R' and c[i][j-1]=='G' and c[i][j]=='W') h[i][j] = 1;
}
for(int i = 1;i <= m;i++) for(int j = 1;j <= n;j++)
{
if(v[i][j]) cv[i][j] = (int)h[i][j]+(int)h[i-1][j+1]+(int)h[i-2][j+2];
if(h[i][j]) ch[i][j] = (int)v[i][j]+(int)v[i+1][j-1]+(int)v[i+2][j-2];
if(v[i][j]){ if(!cv[i][j]) ans++; else if(cv[i][j]==1) s.insert({cv[i][j],i,j,0}); }
if(h[i][j]){ if(!ch[i][j]) ans++; else if(ch[i][j]==1) s.insert({ch[i][j],i,j,1}); }
}
while(!s.empty())
{
ti tt = (*s.begin());
auto &[c,x,y,t] = tt;
ans++;
if(t==0)
{
cv[x][y] = 0;
if(x>2 and y+2<=n and ch[x-2][y+2]) del({ch[x-2][y+2],x-2,y+2,1},tt);
if(x>1 and y+1<=n and ch[x-1][y+1]) del({ch[x-1][y+1],x-1,y+1,1},tt);
if(ch[x][y]) del({ch[x][y],x,y,1},tt);
}
else
{
ch[x][y] = 0;
if(x+2<=m and y>2 and cv[x+2][y-2]) del({cv[x+2][y-2],x+2,y-2,0},tt);
if(x+1<=m and y>1 and cv[x+1][y-1]) del({cv[x+1][y-1],x+1,y-1,0},tt);
if(cv[x][y]) del({cv[x][y],x,y,0},tt);
}
s.erase({c,x,y,t});
}
cout << ans;
}
Compilation message
dango_maker.cpp: In function 'void del(std::tuple<int, int, int, bool>, std::tuple<int, int, int, bool>)':
dango_maker.cpp:15:11: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
auto &[c,x,y,t] = a;
^
dango_maker.cpp:27:17: warning: init-statement in selection statements only available with -std=c++1z or -std=gnu++1z
else if(x>1 and y+1<=n and ch[x-1][y+1]
^
dango_maker.cpp:28:9: error: expected ';' before '{' token
{
^
dango_maker.cpp:27:32: warning: statement has no effect [-Wunused-value]
else if(x>1 and y+1<=n and ch[x-1][y+1]
~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
dango_maker.cpp:32:38: error: expected ')' before ';' token
it = s.find({ch[x][y],x,y,1});
^
dango_maker.cpp:32:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
it = s.find({ch[x][y],x,y,1});
~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:32:12: error: could not convert '(it = s.std::set<std::tuple<int, int, int, bool> >::find(std::tuple<int, int, int, bool>(ch[x][y], (* & x), (* & y), 1)))' from 'std::_Rb_tree_const_iterator<std::tuple<int, int, int, bool> >' to 'bool'
dango_maker.cpp: In function 'int main()':
dango_maker.cpp:90:15: warning: decomposition declaration only available with -std=c++1z or -std=gnu++1z
auto &[c,x,y,t] = tt;
^
