Submission #681783

#	Time	Username	Problem	Language	Result	Execution time	Memory
681783		kym	Robot (JOI21_ho_t4)	C++14	100 / 100	881 ms	120804 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define int long long 
#define FOR(i,s,e) for(int i = s; i <= (int)e; ++i)
#define DEC(i,s,e) for(int i = s; i >= (int)e; --i)
#define IAMSPEED ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
#define db(x) cerr << #x << "=" << x << "\n"
#define db2(x, y) cerr << #x << "=" << x << " , " << #y << "=" << y << "\n"
#define db3(a,b,c) cerr<<#a<<"="<<a<<","<<#b<<"="<<b<<","<<#c<<"="<<c<<"\n"
#define dbv(v) cerr << #v << ":"; for (auto ite : v) cerr << ite << ' '; cerr <<"\n"
#define dbvp(v) cerr << #v << ":"; for (auto ite : v) cerr << "{"  << ite.f << ',' << ite.s << "} "; cerr << "\n"
#define dba(a,ss,ee) cerr << #a << ":"; FOR(ite,ss,ee) cerr << a[ite] << ' '; cerr << "\n"
#define reach cerr << "LINE: " << __LINE__ << "\n";
#else
#define reach 
#define db(x)
#define db2(x,y)
#define db3(a,b,c)
#define dbv(v)
#define dbvp(v)
#define dba(a,ss,ee)
#endif
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define f first 
#define s second
#define g0(x) get<0>(x)
#define g1(x) get<1>(x)
#define g2(x) get<2>(x)
#define g3(x) get<3>(x)
typedef pair <int, int> pi;
typedef tuple<int,int,int> ti3;
typedef tuple<int,int,int,int> ti4;
int rand(int a, int b) { return a + rng() % (b-a+1); }
const int MOD = 1e9 + 7;
const int inf = (int)1e9 + 500;
const long long oo = (long long)1e18 + 500;
template <typename T> bool chmax(T& a, const T b) { return a<b ? a = b, 1 : 0; }
template <typename T> bool chmin(T& a, const T b) { return a>b ? a = b, 1 : 0; }
const int MAXN = 200005;
int n,m;
struct edge{
	int a,b,c,p;
};
 
edge E[MAXN];
vector<pi> V[MAXN];
map<int,int> dist[MAXN]; // 1.
int D[MAXN]; // 0. 
map<int,vector<pi>> T[MAXN];
map<int,int> S[MAXN];
struct state {
	int node;
	bool a;// should this be the one left??
	int color; // what colour is the edge that came in?
	bool operator<(const state& o) const { return node < o.node; } 
};
typedef pair<int,state> pis ;
int32_t main() 
{
	IAMSPEED
	cin >> n >> m;
	FOR(i,1,m) {
		cin >> E[i].a >> E[i].b >> E[i].c >> E[i].p;
		V[E[i].a].pb({E[i].b,i});
		V[E[i].b].pb({E[i].a,i});
	}
	FOR(i,1,n) {
 
		for(auto v:V[i]){
			S[i][E[v.s].c]+=E[v.s].p;
			T[i][E[v.s].c].pb(v);
		}
 
	}
	
	std::priority_queue<pis,vector<pis>,greater<pis>> pq;
	memset(D,-1,sizeof D);
	D[1]=0;
	dist[1][0]=0;
	pq.push(make_pair(0, state({1, 0, 0})));
	pq.push(make_pair(0, state({1, 1, 0})));
	while(pq.size()) { // color is jsut the color you CAME INTO THE NODE with
		pis c=pq.top(); pq.pop();
		state ss=c.s;
		int d=c.f;
		int node=ss.node, z=ss.a;
		int color=ss.color;
		if(z==0){
			if(D[node]!=d)continue;
		} else {
			if(dist[node][color] != d)continue;
		}
		
		if(z){ 
			
			if(T[node][color].size()<=1)continue;
			for(auto v:T[node][color]){ // adj list of this color
				if(v.f == node)continue;
				
 
				int sum=S[node][E[v.s].c]; // take everything
 
				int nx=v.f;
				int nd=d + sum - E[v.s].p; // sum - Px (-Pparent is already done at previous node)
				//auto it=dist[nx][0].find(color);

				if(D[nx] == -1 || D[nx]>nd) {
					D[nx]=nd;
					//if(it!=dist[nx][0].end())it->s=nd;
					//else dist[nx][0][color]=nd;
					pq.push(make_pair(nd, state({nx, 0, color}))); // don't make the other node choose everything
				}
				
				
			}
		} else {
			for(auto v:V[node]) {
				int nx=v.f;
 
				int nd=d;
				int thiscolor=E[v.s].c;
				bool changed=0;
				if(T[node][thiscolor].size()>1) {
					nd += E[v.s].p;
					changed=1;
				}
				
				
				
				if(D[nx] == -1 || D[nx]>min(nd, d + S[node][E[v.s].c] - E[v.s].p)) {
					D[nx]=min(nd, d + S[node][E[v.s].c] - E[v.s].p);
					
					pq.push(make_pair(min(nd, d + S[node][E[v.s].c] - E[v.s].p), state({nx, 0, thiscolor}))); // don't make the other node choose everything
				}
				if(changed){ 
					auto it2=dist[nx].find(thiscolor);
					if(it2 == dist[nx].end() || it2->s>nd-E[v.s].p) {
						if(it2!=dist[nx].end())it2->s=nd-E[v.s].p;
						else dist[nx][thiscolor]=nd-E[v.s].p;
						pq.push(make_pair(nd-E[v.s].p, state({nx, 1, thiscolor})));//yes you must choose everything to get this compensation
					}
				}
 
				
				
			}
		}
	}
	cout << D[n];
}
 
 
 

• Subtask 1: 34 / 34
• Subtask 2: 24 / 24
• Subtask 3: 42 / 42