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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#211667#5472. Secure the Top Secretbulijiojiodibuliduo#WA 1ms3896kbC++179.7kb2023-10-12 20:08:512023-10-12 20:08:51

Judging History

你现在查看的是最新测评结果

  • [2023-10-12 20:08:51]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:3896kb
  • [2023-10-12 20:08:51]
  • 提交

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);
	}
}

詳細信息

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'