#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define sz(x) (int)x.size()
#define getBit(x, i) ((x) >> (i) & 1)
#define rep(i, begin, end) for (ll i = (begin); i <= (end); i++)
#define rrep(i, begin, end) for (ll i = (begin); i >= (end); i--)
typedef long long ll;
typedef pair<int, int> ii;
template <class T>
bool minimize(T &a, const T &b) {
if(a > b) {a = b; return 1;}
return 0;
}
template <class T>
bool maximize(T &a, const T &b) {
if(a < b) {a = b; return 1;}
return 0;
}
const int N = 4e2 + 7, M = 20, oo = 2e9;
int n, m, s, t, res;
int tr[N], c[N][N], f[N][N];
bool st[N], en[N], mid[N], vis[N];
vector<int> adj[N];
string a[N];
bool bfs() {
queue<int> q; q.push(s);
memset(tr, 0, sizeof tr);
memset(vis, 0, sizeof vis);
tr[s] = -1; vis[s] = 1;
while (!q.empty()) {
int u = q.front(); q.pop();
if (u == t) return 1;
rep(v, 0, t) {
if (!vis[v] && c[u][v] > f[u][v]) {
tr[v] = u; vis[v] = 1;
q.push(v);
}
}
}
return 0;
}
void incflow() {
int v = t, dif = oo;
for (; tr[v] != -1; v = tr[v]) {
int u = tr[v];
dif = min(dif, c[u][v] - f[u][v]);
}
v = t; res += dif;
for (; tr[v] != -1; v = tr[v]) {
int u = tr[v];
f[u][v] += dif;
f[v][u] -= dif;
}
}
int g(int x, int y) {
return (x - 1) * m + y;
}
int main() {
ios::sync_with_stdio(0); cin.tie(0);
// freopen("test.inp", "r", stdin);
// freopen("test.out", "w", stdout);
cin >> n >> m;
rep(i, 1, n) cin >> a[i], a[i] = ' ' + a[i];
rep(i, 1, n) rep(j, 1, m) {
// go right
if (j + 2 <= m && a[i].substr(j, 3) == "RGW") {
int fi = g(i, j), se = g(i, j + 1), th = g(i, j + 2);
adj[fi].pb(se); adj[se].pb(th);
c[fi][se] = c[se][fi] = 1;
c[se][th] = c[th][se] = 1;
st[fi] = en[th] = mid[se] = 1;
}
// go down
if (i + 2 <= n && a[i][j] == 'R' && a[i + 1][j] == 'G' && a[i + 2][j] == 'W') {
int fi = g(i, j), se = g(i + 1, j), th = g(i + 2, j);
adj[fi].pb(se); adj[se].pb(th);
c[fi][se] = c[se][fi] = 1;
c[se][th] = c[th][se] = 1;
st[fi] = en[th] = mid[se] = 1;
}
}
t = n * m + 1;
vector<int> node;
rep(i, 1, n * m) {
if (st[i]) {
c[0][i] = c[i][0] = 1;
adj[0].pb(i); adj[i].pb(0);
}
if (en[i]) {
c[i][t] = c[t][i] = 1;
adj[i].pb(t); adj[t].pb(i);
}
if (mid[i] && sz(adj[i]) == 2) node.pb(i);
}
int mx = 0;
rep(i, 0, (1 << sz(node)) - 1) {
memset(f, 0, sizeof f);
rep(j, 0, sz(node) - 1) {
int u = node[j], v = adj[u][getBit(i, j)];
c[u][v] = c[v][u] = 0;
}
res = 0;
while (bfs()) incflow();
maximize(mx, res);
rep(j, 0, sz(node) - 1) {
int u = node[j], v = adj[u][getBit(i, j)];
c[u][v] = c[v][u] = 1;
}
}
cout << mx;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
980 KB |
Output is correct |
2 |
Correct |
1 ms |
980 KB |
Output is correct |
3 |
Correct |
1 ms |
980 KB |
Output is correct |
4 |
Correct |
1 ms |
980 KB |
Output is correct |
5 |
Correct |
1 ms |
980 KB |
Output is correct |
6 |
Correct |
1 ms |
980 KB |
Output is correct |
7 |
Correct |
1 ms |
980 KB |
Output is correct |
8 |
Correct |
1 ms |
988 KB |
Output is correct |
9 |
Correct |
1 ms |
980 KB |
Output is correct |
10 |
Correct |
1 ms |
980 KB |
Output is correct |
11 |
Correct |
1 ms |
988 KB |
Output is correct |
12 |
Correct |
1 ms |
980 KB |
Output is correct |
13 |
Correct |
1 ms |
980 KB |
Output is correct |
14 |
Correct |
1 ms |
980 KB |
Output is correct |
15 |
Correct |
1 ms |
980 KB |
Output is correct |
16 |
Correct |
1 ms |
980 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
980 KB |
Output is correct |
2 |
Correct |
1 ms |
980 KB |
Output is correct |
3 |
Correct |
1 ms |
980 KB |
Output is correct |
4 |
Correct |
1 ms |
980 KB |
Output is correct |
5 |
Correct |
1 ms |
980 KB |
Output is correct |
6 |
Correct |
1 ms |
980 KB |
Output is correct |
7 |
Correct |
1 ms |
980 KB |
Output is correct |
8 |
Correct |
1 ms |
988 KB |
Output is correct |
9 |
Correct |
1 ms |
980 KB |
Output is correct |
10 |
Correct |
1 ms |
980 KB |
Output is correct |
11 |
Correct |
1 ms |
988 KB |
Output is correct |
12 |
Correct |
1 ms |
980 KB |
Output is correct |
13 |
Correct |
1 ms |
980 KB |
Output is correct |
14 |
Correct |
1 ms |
980 KB |
Output is correct |
15 |
Correct |
1 ms |
980 KB |
Output is correct |
16 |
Correct |
1 ms |
980 KB |
Output is correct |
17 |
Correct |
1 ms |
992 KB |
Output is correct |
18 |
Correct |
1 ms |
980 KB |
Output is correct |
19 |
Correct |
1 ms |
1112 KB |
Output is correct |
20 |
Correct |
1 ms |
1108 KB |
Output is correct |
21 |
Correct |
1 ms |
1116 KB |
Output is correct |
22 |
Correct |
1 ms |
1108 KB |
Output is correct |
23 |
Correct |
1 ms |
980 KB |
Output is correct |
24 |
Correct |
1 ms |
980 KB |
Output is correct |
25 |
Correct |
1 ms |
988 KB |
Output is correct |
26 |
Correct |
1 ms |
980 KB |
Output is correct |
27 |
Execution timed out |
2084 ms |
1108 KB |
Time limit exceeded |
28 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
980 KB |
Output is correct |
2 |
Correct |
1 ms |
980 KB |
Output is correct |
3 |
Correct |
1 ms |
980 KB |
Output is correct |
4 |
Correct |
1 ms |
980 KB |
Output is correct |
5 |
Correct |
1 ms |
980 KB |
Output is correct |
6 |
Correct |
1 ms |
980 KB |
Output is correct |
7 |
Correct |
1 ms |
980 KB |
Output is correct |
8 |
Correct |
1 ms |
988 KB |
Output is correct |
9 |
Correct |
1 ms |
980 KB |
Output is correct |
10 |
Correct |
1 ms |
980 KB |
Output is correct |
11 |
Correct |
1 ms |
988 KB |
Output is correct |
12 |
Correct |
1 ms |
980 KB |
Output is correct |
13 |
Correct |
1 ms |
980 KB |
Output is correct |
14 |
Correct |
1 ms |
980 KB |
Output is correct |
15 |
Correct |
1 ms |
980 KB |
Output is correct |
16 |
Correct |
1 ms |
980 KB |
Output is correct |
17 |
Correct |
1 ms |
992 KB |
Output is correct |
18 |
Correct |
1 ms |
980 KB |
Output is correct |
19 |
Correct |
1 ms |
1112 KB |
Output is correct |
20 |
Correct |
1 ms |
1108 KB |
Output is correct |
21 |
Correct |
1 ms |
1116 KB |
Output is correct |
22 |
Correct |
1 ms |
1108 KB |
Output is correct |
23 |
Correct |
1 ms |
980 KB |
Output is correct |
24 |
Correct |
1 ms |
980 KB |
Output is correct |
25 |
Correct |
1 ms |
988 KB |
Output is correct |
26 |
Correct |
1 ms |
980 KB |
Output is correct |
27 |
Execution timed out |
2084 ms |
1108 KB |
Time limit exceeded |
28 |
Halted |
0 ms |
0 KB |
- |