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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#211667 | #5472. Secure the Top Secret | bulijiojiodibuliduo# | WA | 1ms | 3896kb | C++17 | 9.7kb | 2023-10-12 20:08:51 | 2023-10-12 20:08:51 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head
using i64 = long long;
using u8 = unsigned char;
using u32 = unsigned;
using u64 = unsigned long long;
using f80 = long double;
template <
typename CapType, typename TotalCapType,
typename CostType, typename TotalCostType
>
class CostScaling {
private:
static const int alpha = 8; // eps <- max(1, eps / alpha)
using cap_t = CapType;
using tcap_t = TotalCapType;
using cost_t = CostType; // > max{|C|} * (2 * |V|)
using tcost_t = TotalCostType;
static constexpr cost_t Inf = (tcap_t(1) << (sizeof(tcap_t) * 8 - 2)) - 1;
struct InputEdge { int from, to; cap_t b, c; cost_t cost; };
struct Edge { int to, rev; cap_t cap; cost_t cost; };
class Dinic {
public:
Dinic(int N, const vector<int>& ofs, vector<Edge>& edges,
vector<tcap_t>& capacity)
: N(N), ofs(ofs), edges(edges), capacity(capacity), last(N) {}
bool succeeded() {
// s -> u: capacity[u]
// u -> t: capacity[u + N]
tcap_t f = 0;
for (int u = 0; u < N; ++u) f += capacity[u];
vector<int> que(N);
while (f) {
dist.assign(N, -1);
int qh = 0, qt = 0, lv = N;
for (int u = 0; u < N; ++u) if (capacity[u] > 0) que[qt++] = u, dist[u] = 0;
for (; qh < qt; ) {
int u = que[qh++];
if (lv == N && capacity[u + N] > 0) lv = dist[u];
if (dist[u] > lv) break;
for (int ei = ofs[u]; ei < ofs[u + 1]; ++ei) {
int v = edges[ei].to;
if (edges[ei].cap > 0 && dist[v] == -1) {
que[qt++] = v, dist[v] = dist[u] + 1;
}
}
}
if (lv == N) break;
for (int u = 0; u < N; ++u) last[u] = ofs[u];
for (int u = 0; u < N; ++u) if (capacity[u] > 0) {
auto df = block_flow(u, capacity[u]);
f -= df, capacity[u] -= df;
}
}
return f == 0;
}
private:
tcap_t block_flow(int u, tcap_t f) {
tcap_t ret = 0;
if (capacity[u + N] > 0) {
tcap_t df = min(f, capacity[u + N]);
capacity[u + N] -= df;
return df;
}
for (auto& ei = last[u]; ei < ofs[u + 1]; ++ei) {
auto& e = edges[ei]; int v = e.to;
if (e.cap == 0 || dist[v] <= dist[u]) continue;
cap_t df = block_flow(v, min<cap_t>(e.cap, f));
if (df == 0) continue;
e.cap -= df, edges[e.rev].cap += df;
f -= df, ret += df;
if (f == 0) break;
}
return ret;
}
int N;
const vector<int>& ofs;
vector<Edge>& edges;
vector<tcap_t>& capacity;
vector<int> last, dist;
};
public:
CostScaling(int N, int M=0) : N(N), capacity(2 * N) {
if (M > 0) in.reserve(M);
}
void add_directed_edge(int u, int v, cap_t b, cap_t c, cost_t cost) {
if (b > 0) capacity[v] += b, capacity[u + N] += b;
else capacity[u] += -b, capacity[v + N] += -b;
in.push_back({u, v, b, c, cost});
}
pair<bool, tcost_t> minimum_cost_circulation() {
construct();
if (!has_feasible_circulation()) return {false, 0};
const int cost_multiplier = 2 << (31-__builtin_clz(N)); // should be > |V|
assert(cost_multiplier>=N);
cost_t eps = 0;
for (auto& e : edges) e.cost *= cost_multiplier, eps = max(eps, e.cost);
while (eps > 1) refine(eps = max<cost_t>(1, eps / alpha));
tcost_t ret = initial_cost;
for (auto& e : edges) ret -= (e.cost / cost_multiplier) * e.cap;
return {true, ret / 2};
}
private:
void refine(const cost_t eps) {
auto cost_p = [&] (int u, const Edge& e) {
return e.cost + potential[u] - potential[e.to];
};
for (int u = 0; u < N; ++u) for (int i = ofs[u]; i < ofs[u + 1]; ++i) {
auto& e = edges[i];
if (cost_p(u, e) < 0) edges[e.rev].cap += e.cap, e.cap = 0;
}
vector<tcap_t> excess(initial_excess);
for (auto& e : edges) excess[e.to] -= e.cap;
vector<int> stack; stack.reserve(N);
for (int u = 0; u < N; ++u) if (excess[u] > 0) stack.push_back(u);
auto residue = [&] (const Edge& e) -> cap_t { return e.cap; };
auto push = [&] (int u, Edge& e, cap_t df) {
e.cap -= df; edges[e.rev].cap += df;
excess[e.to] += df; excess[u] -= df;
if (excess[e.to] > 0 && excess[e.to] <= df) {
stack.push_back(e.to);
}
};
auto relabel = [&] (int u, cost_t delta) {
potential[u] -= delta + eps;
};
auto relabel_in_advance = [&] (int u) {
if (excess[u] != 0) return false;
auto delta = Inf;
for (int ei = ofs[u]; ei < ofs[u + 1]; ++ei) {
auto& e = edges[ei];
if (residue(e) == 0) continue;
if (cost_p(u, e) < 0) return false;
else delta = min<tcost_t>(delta, cost_p(u, e));
}
relabel(u, delta);
return true;
};
auto discharge = [&] (int u) {
auto delta = Inf;
for (int ei = ofs[u]; ei < ofs[u + 1]; ++ei) {
auto& e = edges[ei];
if (residue(e) == 0) continue;
if (cost_p(u, e) < 0) {
if (relabel_in_advance(e.to)) {
--ei; continue; // modify ei (!)
}
cap_t df = min<tcap_t>(excess[u], residue(e));
push(u, e, df);
if (!excess[u]) return;
} else delta = min<tcost_t>(delta, cost_p(u, e));
}
relabel(u, delta);
stack.push_back(u);
};
while (!stack.empty()) {
auto u = stack.back(); stack.pop_back();
discharge(u);
}
}
void construct() {
ofs.assign(N + 1, 0);
edges.resize(2 * in.size());
initial_excess.assign(N, 0);
initial_cost = 0;
potential.assign(N, 0);
for (auto& e : in) ofs[e.from + 1]++, ofs[e.to + 1]++;
for (int i = 1; i <= N; ++i) ofs[i] += ofs[i - 1];
for (auto& e : in) {
initial_excess[e.to] += e.c;
initial_excess[e.from] += -e.b;
initial_cost += tcost_t(e.cost) * (e.c + e.b);
edges[ofs[e.from]++] = {e.to, ofs[e.to], e.c - e.b, e.cost};
edges[ofs[e.to]++] = {e.from, ofs[e.from] - 1, 0, -e.cost};
}
for (int i = N; i > 0; --i) ofs[i] = ofs[i - 1];
ofs[0] = 0;
}
bool has_feasible_circulation() {
return Dinic(N, ofs, edges, capacity).succeeded();
}
private:
int N;
vector<InputEdge> in;
vector<tcap_t> capacity;
vector<int> ofs;
vector<Edge> edges;
tcost_t initial_cost;
vector<tcap_t> initial_excess;
vector<tcost_t> potential;
};
// cap, total_cap, cost * (2 * |V|), total_cost
using MCC = CostScaling<int64_t, int64_t, int64_t, int64_t>;
// using MCC = CostScaling<int, int, int, int>;
const int N=110;
int n,m,k;
char s[N][N];
bool hor[N][N],ver[N][N];
const ll inf=1000000000;
PII dir[4]={{-1,0},{0,1},{1,0},{0,-1}};
bool inside(int x,int y) {
return x>=0&&x<n&&y>=0&&y<m;
}
int main() {
scanf("%d%d",&n,&m);
rep(i,0,n) scanf("%s",s[i]);
scanf("%d",&k);
rep(i,0,k) {
int x,y;
static char t[11];
scanf("%d%d%s",&x,&y,t);
--x; --y;
if (t[0]=='b') ver[x][y]=1;
else hor[x][y]=1;
}
PII sp,tp,up;
rep(i,0,n) rep(j,0,m) {
if (s[i][j]=='S') sp=mp(i,j);
if (s[i][j]=='T') tp=mp(i,j);
if (s[i][j]=='U') up=mp(i,j);
}
vector<PII> bor;
PII pos=sp;
int d=0;
while (inside(sp.fi+dir[d].fi,sp.se+dir[d].se)) ++d;
while (1) {
bor.pb(pos);
while (!inside(pos.fi+dir[d].fi,pos.se+dir[d].se)||s[pos.fi+dir[d].fi][pos.se+dir[d].se]=='#') d=(d+1)%4;
pos.fi+=dir[d].fi; pos.se+=dir[d].se;
d=(d+3)%4;
//printf("%d %d\n",pos.fi,pos.se);
if (pos==sp) break;
}
if (find(all(bor),tp)==bor.end()) {
puts("-1");
return 0;
}
if (find(all(bor),up)==bor.end()) {
puts("0");
return 0;
}
auto t1=find(all(bor),tp)-bor.begin();
auto t2=find(all(bor),up)-bor.begin();
if (t1>t2) reverse(bor.begin()+1,bor.end());
rep(i,0,SZ(bor)-1) {
auto [x1,y1]=bor[i];
auto [x2,y2]=bor[i+1];
if (bor[i]==up) {
puts("-1");
return 0;
}
//printf("%d %d %d %d\n",x1,y1,x2,y2);
if (x1==x2) hor[x1][min(y1,y2)]=0;
if (y1==y2) ver[min(x1,x2)][y1]=0;
if (bor[i+1]==tp) break;
}
int S=sp.fi*m+sp.se,T=up.fi*m+up.se;
MCC mcc(n*m);
rep(i,0,n) rep(j,0,m) {
if (i+1<n&&s[i][j]!='#'&&s[i+1][j]!='#') {
int u=i*m+j,v=i*m+j+m;
if (!ver[i][j]) {
mcc.add_directed_edge(u,v,0,inf,0);
mcc.add_directed_edge(v,u,0,inf,0);
} else {
mcc.add_directed_edge(u,v,0,inf,1);
mcc.add_directed_edge(v,u,0,inf,1);
mcc.add_directed_edge(u,v,0,1,0);
mcc.add_directed_edge(v,u,0,1,0);
}
}
if (j+1<m&&s[i][j]!='#'&&s[i][j+1]!='#') {
int u=i*m+j,v=i*m+j+1;
if (!hor[i][j]) {
mcc.add_directed_edge(u,v,0,inf,0);
mcc.add_directed_edge(v,u,0,inf,0);
} else {
mcc.add_directed_edge(u,v,0,inf,1);
mcc.add_directed_edge(v,u,0,inf,1);
mcc.add_directed_edge(u,v,0,1,0);
mcc.add_directed_edge(v,u,0,1,0);
}
}
}
mcc.add_directed_edge(S,T,0,inf,-2);
auto ret=mcc.minimum_cost_circulation();
ret.se=-ret.se;
//printf("%lld\n",d.se);
if (!ret.fi) puts("-1"); else {
if (ret.se>=100000) puts("-1");
else printf("%lld\n",ret.se);
}
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 3872kb
input:
3 3 S.. #.. U.T 7 1 2 b 1 3 b 2 2 b 2 2 r 2 3 b 3 1 r 3 2 r
output:
3
result:
ok single line: '3'
Test #2:
score: 0
Accepted
time: 0ms
memory: 3688kb
input:
2 2 ST .U 4 1 1 r 1 1 b 1 2 b 2 1 r
output:
-1
result:
ok single line: '-1'
Test #3:
score: 0
Accepted
time: 1ms
memory: 3896kb
input:
7 10 U......... .......... ###....... .......... .......### .......... S........T 18 4 4 r 5 4 r 6 7 r 7 7 r 3 4 b 3 5 b 3 6 b 3 7 b 3 8 b 3 9 b 3 10 b 5 1 b 5 2 b 5 3 b 5 4 b 5 5 b 5 6 b 5 7 b
output:
14
result:
ok single line: '14'
Test #4:
score: 0
Accepted
time: 0ms
memory: 3748kb
input:
2 5 .T.#S ....U 10 1 3 b 1 1 r 1 1 b 2 1 r 1 2 b 1 5 b 2 2 r 1 2 r 2 3 r 2 4 r
output:
-1
result:
ok single line: '-1'
Test #5:
score: 0
Accepted
time: 0ms
memory: 3748kb
input:
5 5 U.S.. ..... ..... ..... .T... 12 2 4 b 4 1 b 2 2 r 1 5 b 2 2 b 4 3 b 5 3 r 1 2 b 3 2 r 2 1 r 3 3 r 2 4 r
output:
-1
result:
ok single line: '-1'
Test #6:
score: 0
Accepted
time: 0ms
memory: 3684kb
input:
5 4 .... ...U .... S#.. .#T. 12 3 4 b 2 1 b 4 3 r 2 2 b 4 3 b 3 3 r 2 3 r 1 1 b 2 2 r 4 4 b 3 1 b 1 3 r
output:
-1
result:
ok single line: '-1'
Test #7:
score: -100
Wrong Answer
time: 0ms
memory: 3676kb
input:
3 3 UST ### .#. 2 1 1 r 1 2 r
output:
0
result:
wrong answer 1st lines differ - expected: '-1', found: '0'