#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define ll long long
#define f first
#define s second
#define FOR(i,a,b) for (int i = a; i<b; i++)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) for (int i = n-1; i>=0; i--)
#define SZ(x) (int)(x.size())
#define ALL(x) x.begin(),x.end()
#define MX(a,b) a = max(a,(__typeof__(a))(b))
#define MN(a,b) a = min(a,(__typeof__(a))(b))
#define pb push_back
#ifdef BALBIT
#define IOS()
#define bug(x) cerr<<__LINE__<<' '<<#x<<": "<<x<<endl
#else
#define IOS() ios::sync_with_stdio(0),cin.tie(0)
#define endl '\n'
#define bug(x)
#endif
const ll mod = 1e9+7;
const int maxn = 3e3+5;
const ll INF = 0x3f3f3f3f3f3f3f3f;
const int iinf = 0x3f3f3f3f;
struct Dinic{
struct Edge{
int to, rev; int cap; int flow = 0;
Edge(int to, int rev, int cap) : to(to),rev(rev),cap(cap){
}
};
int n , S, T;
vector<vector<Edge> > g;
vector<int> level;
vector<int> ptr;
Dinic(int n, int S, int T) : n(n), S(S), T(T){
g.resize(n); level.resize(n); ptr.resize(n);
}
void add(int v, int u, int cap){
g[v].pb({u,SZ(g[u]), cap});
g[u].pb({v,SZ(g[v])-1, 0});
}
bool bfs(){
fill(ALL(level), -1);
level[S]=0;
queue<int> q ({S});
while (level[T]==-1 && !q.empty() ){
int v = q.front(); q.pop();
for (Edge &e : g[v]){
if(e.cap-e.flow > 0 && level[e.to] == -1){
level[e.to] = level[v]+1;
q.push(e.to);
}
}
}
return level[T]!=-1;
}
int dfs(int v, int amt){
if(amt == 0 || v== T) return amt;
for(; ptr[v] < SZ(g[v]); ptr[v]++){
Edge &e = g[v][ptr[v]];
if (level[e.to]!=level[v]+1) continue;
int mo = dfs(e.to, min(amt,e.cap-e.flow));
if (mo !=0 ) {
e.flow += mo;
g[e.to][e.rev].flow -= mo;
return mo;
}
}
return 0;
}
int mf(){
int re = 0;
while (bfs()){
fill(ALL(ptr),0);
while(int amt = dfs(S,iinf)) {
re += amt;
}
}
return re;
}
};
char grd[maxn][maxn];
int idup[maxn][maxn];
int idrt[maxn][maxn];
signed main(){
IOS();
int n, m; cin>>n>>m;
REP(i,n) REP(j,m) cin>>grd[i][j];
int nup = 0, nrt = 0;
REP(i,n)REP(j,m){
idup[i][j] = idrt[i][j] = -1;
if(grd[i][j]=='G'){
if (i && i!=n-1 && grd[i-1][j] == 'R' && grd[i+1][j]=='W' ) {
idup[i][j] = nup++;
}
if (j && j!=m-1 && grd[i][j-1] == 'R' && grd[i][j+1]=='W' ) {
idrt[i][j] = nrt ++;
}
}
}
int N = nup + nrt + 5; int S = N-1, T = N-2;
Dinic dd (N,S,T);
REP(i,n) REP(j,m){
if(idup[i][j]!=-1){
// cout<<i<<' '<<j<<' '<<idup[i][j]<<endl;
dd.add(S,idup[i][j],1);
if(idrt[i][j] != -1) {
dd.add(idup[i][j], idrt[i][j] + nup, iinf);
}
if(i && idrt[i-1][j+1]!=-1){
dd.add(idup[i][j], idrt[i-1][j+1] + nup, iinf);
}
if(j && idrt[i+1][j-1]!=-1){
dd.add(idup[i][j], idrt[i+1][j-1] + nup, iinf);
}
}
if(idrt[i][j]!=-1){
dd.add(idrt[i][j] + nup, T, 1);
}
}
cout<<nup + nrt - dd.mf() << endl;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
376 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
376 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
296 KB |
Output is correct |
15 |
Correct |
4 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
376 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
376 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
296 KB |
Output is correct |
15 |
Correct |
4 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
376 KB |
Output is correct |
18 |
Incorrect |
2 ms |
380 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
376 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
376 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
296 KB |
Output is correct |
15 |
Correct |
4 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
376 KB |
Output is correct |
18 |
Incorrect |
2 ms |
380 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |