結果
| 問題 |
No.1599 Hikyaku
|
| コンテスト | |
| ユーザー |
Nachia
|
| 提出日時 | 2022-01-31 00:28:37 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 1,363 ms / 7,500 ms |
| コード長 | 6,563 bytes |
| コンパイル時間 | 1,750 ms |
| コンパイル使用メモリ | 94,968 KB |
| 最終ジャッジ日時 | 2025-01-27 17:57:56 |
|
ジャッジサーバーID (参考情報) |
judge1 / judge5 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 4 |
| other | AC * 49 |
ソースコード
#include <vector>
#include <utility>
namespace nachia{
struct AdjacencyList{
public:
struct AdjacencyListRange{
using iterator = typename std::vector<int>::const_iterator;
iterator begi, endi;
iterator begin() const { return begi; }
iterator end() const { return endi; }
int size() const { return (int)std::distance(begi, endi); }
const int& operator[](int i) const { return begi[i]; }
};
private:
int mn;
std::vector<int> E;
std::vector<int> I;
public:
AdjacencyList(int n, std::vector<std::pair<int,int>> edges, bool rev){
mn = n;
std::vector<int> buf(n+1, 0);
for(auto [u,v] : edges){ ++buf[u]; if(rev) ++buf[v]; }
for(int i=1; i<=n; i++) buf[i] += buf[i-1];
E.resize(buf[n]);
for(int i=(int)edges.size()-1; i>=0; i--){
auto [u,v] = edges[i];
E[--buf[u]] = v;
if(rev) E[--buf[v]] = u;
}
I = std::move(buf);
}
AdjacencyList(const std::vector<std::vector<int>>& edges = {}){
int n = mn = edges.size();
std::vector<int> buf(n+1, 0);
for(int i=0; i<n; i++) buf[i+1] = buf[i] + edges[i].size();
E.resize(buf[n]);
for(int i=0; i<n; i++) for(int j=0; j<(int)edges[i].size(); j++) E[buf[i]+j] = edges[i][j];
I = std::move(buf);
}
AdjacencyListRange operator[](int u) const {
return AdjacencyListRange{ E.begin() + I[u], E.begin() + I[u+1] };
}
int num_vertices() const { return mn; }
int num_edges() const { return E.size(); }
AdjacencyList reversed_edges() const {
AdjacencyList res;
int n = res.mn = mn;
std::vector<int> buf(n+1, 0);
for(int v : E) ++buf[v];
for(int i=1; i<=n; i++) buf[i] += buf[i-1];
res.E.resize(buf[n]);
for(int u=0; u<n; u++) for(int v : operator[](u)) res.E[--buf[v]] = u;
res.I = std::move(buf);
return res;
}
};
struct AdjacencyListEdgeIndexed{
public:
struct Edge { int to; int edgeidx; };
struct AdjacencyListRange{
using iterator = typename std::vector<Edge>::const_iterator;
iterator begi, endi;
iterator begin() const { return begi; }
iterator end() const { return endi; }
int size() const { return (int)std::distance(begi, endi); }
const Edge& operator[](int i) const { return begi[i]; }
};
private:
int mn;
std::vector<Edge> E;
std::vector<int> I;
public:
AdjacencyListEdgeIndexed(int n, const std::vector<std::pair<int,int>>& edges, bool rev){
mn = n;
std::vector<int> buf(n+1, 0);
for(auto [u,v] : edges){ ++buf[u]; if(rev) ++buf[v]; }
for(int i=1; i<=n; i++) buf[i] += buf[i-1];
E.resize(buf[n]);
for(int i=(int)edges.size()-1; i>=0; i--){
auto [u,v] = edges[i];
E[--buf[u]] = { v, i };
if(rev) E[--buf[v]] = { u, i };
}
I = std::move(buf);
}
AdjacencyListEdgeIndexed() : AdjacencyListEdgeIndexed(0, {}, false) {}
AdjacencyListRange operator[](int u) const {
return AdjacencyListRange{ E.begin() + I[u], E.begin() + I[u+1] };
}
int num_vertices() const { return mn; }
int num_edges() const { return E.size(); }
AdjacencyListEdgeIndexed reversed_edges() const {
AdjacencyListEdgeIndexed res;
int n = res.mn = mn;
std::vector<int> buf(n+1, 0);
for(auto [v,i] : E) ++buf[v];
for(int i=1; i<=n; i++) buf[i] += buf[i-1];
res.E.resize(buf[n]);
for(int u=0; u<n; u++) for(auto [v,i] : operator[](u)) res.E[--buf[v]] = {u,i};
res.I = std::move(buf);
return res;
}
};
} // namespace nachia
#include <iostream>
#include <queue>
using namespace std;
using ll = long long;
using ull = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)
template<class T>
using nega_queue = priority_queue<T,vector<T>,greater<T>>;
const int INF = 1001001001;
const int W = 600;
const int H = 600;
const int NV = W * H; // number of vertices
const int maxV = 7;
struct Start{ int id,v; };
int pos2id(int y,int x){ return y * W + x; }
int X,Y;
int N;
vector<Start> hikyaku;
double dt[maxV];
double V[maxV];
double T[maxV][NV];
nachia::AdjacencyList E;
double D[maxV][NV];
int main(){
cin >> X >> Y; X--; Y--;
cin >> N;
{
vector<pair<int,int>> edges;
rep(y,H) rep(x,W-1) edges.push_back({ pos2id(y,x), pos2id(y,x+1) });
rep(y,H-1) rep(x,W) edges.push_back({ pos2id(y,x), pos2id(y+1,x) });
E = nachia::AdjacencyList(NV, edges, true);
}
hikyaku.resize(N);
rep(i,N){
int x,y,v; cin >> x >> y >> v;
x--; y--; v--;
hikyaku[i] = { pos2id(y,x),v };
}
rep(v,maxV) V[v] = 1+v;
rep(v,maxV) dt[v] = 1000.0 / (1+v);
rep(v,maxV) rep(i,NV) T[v][i] = INF;
{
vector<vector<int>> I(maxV);
for(auto a : hikyaku){
I[a.v].push_back(a.id);
T[a.v][a.id] = 0;
}
rep(v,maxV){
rep(i,I[v].size()){
int p = I[v][i];
for(int e : E[p]) if(T[v][e] >= INF - 1.0){
T[v][e] = T[v][p] + dt[v];
I[v].push_back(e);
}
}
}
}
rep(v,maxV) rep(i,NV) D[v][i] = INF;
nega_queue<pair<double,pair<int,int>>> Q;
D[hikyaku[0].v][hikyaku[0].id] = 0.0;
Q.push(make_pair(0.0,make_pair(hikyaku[0].v,hikyaku[0].id)));
while(Q.size()){
double d = Q.top().first;
int v = Q.top().second.first;
int p = Q.top().second.second;
Q.pop();
if(D[v][p] != d) continue;
for(int nxv=v+1; nxv<maxV; nxv++) if(D[nxv][p] > max(T[nxv][p],d)){
D[nxv][p] = max(T[nxv][p],d);
Q.push(make_pair(D[nxv][p],make_pair(nxv,p)));
}
for(int e : E[p]){
if(D[v][e] > d + dt[v]){
D[v][e] = d + dt[v];
Q.push(make_pair(D[v][e],make_pair(v,e)));
}
double nxd = dt[v];
int pv = v;
for(int nxv=v+1; nxv<maxV; nxv++){
double t0 = d + nxd - max(d - dt[nxv], T[nxv][e]);
if(t0 < 0) continue;
t0 = min(t0,dt[pv]+dt[nxv]);
double t = nxd - t0 * (V[nxv] - V[pv]) / (V[nxv] + V[pv]);
nxd = t; pv = nxv;
if(D[nxv][e] <= d+nxd) continue;
D[nxv][e] = d+nxd;
Q.push(make_pair(d+nxd,make_pair(nxv,e)));
}
}
}
double ans = INF;
rep(v,maxV) ans = min(ans,D[v][pos2id(Y,X)]);
cout.precision(10); cout << fixed;
cout << ans << endl;
return 0;
}
struct ios_do_not_sync{
ios_do_not_sync(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
}
} ios_do_not_sync_inst;
Nachia