oj.uz

Submission #241453

# Submission time Handle Problem Language Result Execution time Memory
241453 2020-06-24T08:12:35 Z kal013 Olympic Bus (JOI20_ho_t4) C++17
100 / 100
 745 ms 6780 KB 
/*/ Author: kal013 /*/
// #pragma GCC optimize ("O3")
#include "bits/stdc++.h"
#include "ext/pb_ds/assoc_container.hpp"
#include "ext/pb_ds/tree_policy.hpp"
using namespace std;
using namespace __gnu_pbds;

template<class T> 
using ordered_set = tree<T, null_type,less<T>, rb_tree_tag,tree_order_statistics_node_update> ;

template<class key, class value, class cmp = std::less<key>>
using ordered_map = tree<key, value, cmp, rb_tree_tag, tree_order_statistics_node_update>;
// find_by_order(k)  returns iterator to kth element starting from 0;
// order_of_key(k) returns count of elements strictly smaller than k;

template<class T>
using min_heap = priority_queue<T, vector<T> , greater<T> >;

struct custom_hash { // Credits: https://codeforces.com/blog/entry/62393
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

template<class T> ostream& operator<<(ostream &os, vector<T> V) {
    os << "[ ";
    for(auto v : V) os << v << " ";
    return os << "]";
}
template<class T> ostream& operator<<(ostream &os, set<T> S){
    os << "{ ";
    for(auto s:S) os<<s<<" ";
    return os<<"}";
}
template<class T> ostream& operator<<(ostream &os, unordered_set<T> S){
    os << "{ ";
    for(auto s:S) os<<s<<" ";
    return os<<"}";
}
template<class T> ostream& operator<<(ostream &os, ordered_set<T> S){
    os << "{ ";
    for(auto s:S) os<<s<<" ";
    return os<<"}";
}
template<class L, class R> ostream& operator<<(ostream &os, pair<L,R> P) {
    return os << "(" << P.first << "," << P.second << ")";
}
template<class L, class R> ostream& operator<<(ostream &os, map<L,R> M) {
    os << "{ ";
    for(auto m:M) os<<"("<<m.first<<":"<<m.second<<") ";
    return os<<"}";
}
template<class L, class R> ostream& operator<<(ostream &os, unordered_map<L,R> M) {
    os << "{ ";
    for(auto m:M) os<<"("<<m.first<<":"<<m.second<<") ";
    return os<<"}";
}
template<class L, class R, class chash = std::hash<R> > ostream& operator<<(ostream &os, gp_hash_table<L,R,chash> M) {
    os << "{ ";
    for(auto m:M) os<<"("<<m.first<<":"<<m.second<<") ";
    return os<<"}";
}

#define TRACE
#ifdef TRACE
    #define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
    template <typename Arg1>
    void __f(const char* name, Arg1&& arg1){
        cerr << name << " : " << arg1 << endl;
    }
    template <typename Arg1, typename... Args>
    void __f(const char* names, Arg1&& arg1, Args&&... args){
        const char* comma = strchr(names + 1, ',');
        cerr.write(names, comma - names) << " : " << arg1<<" | ";
        __f(comma+1, args...);
    }
#else
    #define trace(...) 1
#endif

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

inline int64_t random_long(long long l,long long r){
    uniform_int_distribution<int64_t> generator(l,r);
    return generator(rng);
}
inline int64_t random_long(){
    uniform_int_distribution<int64_t> generator(LLONG_MIN,LLONG_MAX);
    return generator(rng);
}


/*/---------------------------Defines----------------------/*/
typedef vector<int> vi;
typedef pair<int,int> pii;

#define ll long long
#define F first
#define S second
#define pb push_back
#define endl "\n"
#define all(v) (v).begin(),(v).end()
/*/-----------------------Modular Arithmetic---------------/*/

const int mod=1e9+7;
inline int add(int x,int y){
    x+=y;
    if (x>=mod) return x-mod;
    return x;
}
inline int sub(int x,int y){
    x-=y;
    if (x<0) return x+mod;
    return x;
}
inline int mul(int x,int y){
    return (x*1ll*y)%mod;
}
inline int power(int x,int y){
    int ans=1;
    while(y){
        if (y&1) ans=mul(ans,x);
        x=mul(x,x);
        y>>=1;
    }
    return ans;
}
inline int inv(int x){
    return power(x,mod-2);
}
/*/-----------------------------Code begins----------------------------------/*/
const int N = 210;
const int M = 5e4+100;
vector<int> adj[N][2];

vector<int> g[N];
const ll INF = 1e15+2;

ll dis[N][N];

int U[M][2]; 
ll C[M],D[M];




ll dp[2][N][N][2];

ll compress[2][2][M];


ll dist[N];
int par[N];

bitset<M> vis;


void init_dijkstra(int src,int n,int idx,int ignore_edge, bool do_par,bool prev_init = false){
	// assert(src == 1 || src == n);
	// assert(idx == 0 || idx == 1);
	// assert(n < N && ignore_edge < M);
	min_heap<pair<ll,ll> > queue;

	if (!prev_init){
		for(int i = 1; i <= n; ++i){
			dist[i] = INF;
			if (do_par) par[i] = -1;
		}
		dist[src] = 0;


		queue.push({0,src});
	}
	else{
		vector<int> ex,rem;
		for(int i = 1;  i<=n; ++i){
			if (dist[i] < INF){
				ex.push_back(i);
			}
			else{
				rem.push_back(i);
			}
		}

		for(auto X: ex){
			for(auto i : adj[X][idx]){
				if (i == ignore_edge) continue;
				int v = U[i][0]^U[i][1]^X;
				dist[v] = min(dist[v],dist[X] + C[i]);
			}
		}



		for(auto vv: rem){
			queue.push({dist[vv],vv});
		}
	}
	

	while(!queue.empty()){
		auto X = queue.top();
		queue.pop();
		if (X.first > dist[X.second]) continue;
		if (X.first >= INF) break;
		// assert(dist[X.second] == X.first);


		for(auto i: adj[X.second][idx]){
			if (i == ignore_edge) continue;
			int v = U[i][0]^U[i][1]^X.second;
			
			// assert( 1 <= v && v <= n);

			if (dist[v] > dist[X.second] + C[i]){
				dist[v] = dist[X.second] + C[i];

				queue.push({dist[v],v});
				if (do_par) par[v] = i;
			}

		}
	}


}

void do_dp(int idx,int src,int n,int m){
	// assert( idx == 0 || idx == 1);
	// assert(src == 1 || src == n);
	int s_id = (src == 1) ? 0 : 1;

	init_dijkstra(src,n,idx,m + 10,true);

	for(int i = 0; i<= m; ++i){
		vis[i] = false;
	}
	vector<int> used;

	for(int i = 1; i<=n; ++i){
		g[i].clear();
	}

	for(int zz = 1; zz <= n ; ++zz){
		auto e = par[zz];
		if (e != -1) {
			// assert(zz != src);
			// assert(0 <= e && e < m); 
			int v = U[e][0] ^ U[e][1] ^ zz;
			g[v].push_back(zz);

			used.push_back(e); 
			vis[e] = true;
		}
	}
	// assert(used.size() < n);
	for(int i = 0; i<m ;++i){
		if (!vis[i]){
			compress[idx][s_id][i] = 0;
			
		}
	}

	for(int z = 1; z <= n; ++z){
		dp[idx][z][0][s_id] = dist[z];
	}


	int cntr = 1;
	for(auto e: used){

		int u = U[e][idx], v = U[e][idx^1];
		assert(par[v] == e);

		for(int i = 1; i <= n; ++i){
			dist[i] = dp[idx][i][0][s_id];
		}

		vector<int> bfs = {v};

		for(int i = 0; i < bfs.size() ; ++i){
			int cur = bfs[i];
			dist[cur] = INF;	
			for(auto edge : g[cur]){
				bfs.push_back(edge);
			}
		}

		bfs.clear();

		init_dijkstra(src,n,idx,e,false,true);
		
		compress[idx][s_id][e] = cntr;


		for(int z = 1; z <= n; ++z){
			dp[idx][z][cntr][s_id] = dist[z];
		}

		++cntr;

	}





}


inline ll get_dp_val(ll idx,ll n,ll m, ll s_id){
	ll cntr = compress[idx][s_id][m];

	return dp[idx][n][cntr][s_id];
}

void solve(){
    int n,m;
    cin>>n>>m;
    // assert( n < N && m < M);
    for(int i = 1; i<=n ; ++i){
    	for(int j = 1; j<=n ; ++j){
    		dis[i][j] = INF;
    	}
    	dis[i][i] = 0;
    }

    for(int i = 0; i < m; ++i){
    	cin>>U[i][0]>>U[i][1]>>C[i]>>D[i];
    	ll u = U[i][0], v = U[i][1];

    	// assert(1 <= u && u <= n && 1 <= v && v <= n);
    	dis[u][v] = min(dis[u][v], C[i]);

    	adj[u][0].push_back(i);
    	adj[v][1].push_back(i);
    }

    for(int mid = 1; mid <= n; ++mid){
    	for(int src = 1; src <= n; ++src){
    		for(int des = 1; des <= n ; ++des){
    			dis[src][des] = min(dis[src][mid] + dis[mid][des],dis[src][des]);
    		}
    	}
    }

    ll ans = min(INF, dis[1][n] + dis[n][1]);
    do_dp(0,1,n,m);
    do_dp(0,n,n,m);
    do_dp(1,1,n,m);
    do_dp(1,n,n,m);


    for(int i = 0; i < m; ++i){
    	ll u = U[i][0], v = U[i][1];

    	ll cur_s_t = get_dp_val(0,n,i,0);
    	cur_s_t = min(cur_s_t, get_dp_val(0,v,i,0) + get_dp_val(1,u,i,1) + C[i]);


    	ll cur_t_s = get_dp_val(0,1,i,1);

    	cur_t_s = min(cur_t_s, get_dp_val(0,v,i,1) + get_dp_val(1,u,i,0) + C[i]);

    	ans = min(ans, cur_t_s + cur_s_t + D[i]);
    }
    if (ans >= INF){
    	ans = -1;
    }
    cout<<ans<<endl;
}
int main(){
    // Use "set_name".max_load_factor(0.25);"set_name".reserve(512); with unordered set
    // Or use gp_hash_table<X,null_type>
    ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
    cout<<fixed<<setprecision(25);
    cerr<<fixed<<setprecision(10);
    auto start = std::chrono::high_resolution_clock::now();
    int t=1;
    // cin>>t;
    while(t--) {
        solve();
    }
    auto stop = std::chrono::high_resolution_clock::now(); 
    auto duration = std::chrono::duration_cast<std::chrono::nanoseconds>(stop - start); 
    
    // cerr << "Time taken : " << ((long double)duration.count())/((long double) 1e9) <<"s "<< endl;     
}

Compilation message

ho_t4.cpp: In function 'void do_dp(int, int, int, int)':
ho_t4.cpp:291:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < bfs.size() ; ++i){
                  ~~^~~~~~~~~~~~
ho_t4.cpp:282:7: warning: unused variable 'u' [-Wunused-variable]
   int u = U[e][idx], v = U[e][idx^1];
       ^

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 2168 KB Output is correct
2 Correct 15 ms 2048 KB Output is correct
3 Correct 25 ms 2176 KB Output is correct
4 Correct 25 ms 2176 KB Output is correct
5 Correct 6 ms 768 KB Output is correct
6 Correct 18 ms 2048 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 6 ms 512 KB Output is correct
10 Correct 46 ms 2168 KB Output is correct
11 Correct 45 ms 2168 KB Output is correct
12 Correct 44 ms 2168 KB Output is correct
13 Correct 19 ms 2176 KB Output is correct
14 Correct 22 ms 2176 KB Output is correct
15 Correct 22 ms 2176 KB Output is correct
16 Correct 23 ms 2176 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 488 ms 5496 KB Output is correct
2 Correct 507 ms 5496 KB Output is correct
3 Correct 471 ms 5624 KB Output is correct
4 Correct 32 ms 2176 KB Output is correct
5 Correct 24 ms 2176 KB Output is correct
6 Correct 17 ms 2048 KB Output is correct
7 Correct 15 ms 2048 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 118 ms 5368 KB Output is correct
10 Correct 101 ms 5372 KB Output is correct
11 Correct 317 ms 5368 KB Output is correct
12 Correct 323 ms 5496 KB Output is correct
13 Correct 327 ms 5472 KB Output is correct
14 Correct 295 ms 5496 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 26 ms 2176 KB Output is correct
2 Correct 18 ms 2176 KB Output is correct
3 Correct 467 ms 4600 KB Output is correct
4 Correct 16 ms 2048 KB Output is correct
5 Correct 641 ms 5368 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 5 ms 436 KB Output is correct
8 Correct 112 ms 5540 KB Output is correct
9 Correct 144 ms 5344 KB Output is correct
10 Correct 409 ms 5496 KB Output is correct
11 Correct 416 ms 5432 KB Output is correct
12 Correct 294 ms 5624 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 5 ms 384 KB Output is correct
17 Correct 5 ms 384 KB Output is correct
18 Correct 5 ms 384 KB Output is correct
19 Correct 424 ms 5496 KB Output is correct
20 Correct 410 ms 5468 KB Output is correct
21 Correct 313 ms 5624 KB Output is correct
22 Correct 410 ms 5496 KB Output is correct

Subtask #4
63.0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 2168 KB Output is correct
2 Correct 15 ms 2048 KB Output is correct
3 Correct 25 ms 2176 KB Output is correct
4 Correct 25 ms 2176 KB Output is correct
5 Correct 6 ms 768 KB Output is correct
6 Correct 18 ms 2048 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 6 ms 512 KB Output is correct
10 Correct 46 ms 2168 KB Output is correct
11 Correct 45 ms 2168 KB Output is correct
12 Correct 44 ms 2168 KB Output is correct
13 Correct 19 ms 2176 KB Output is correct
14 Correct 22 ms 2176 KB Output is correct
15 Correct 22 ms 2176 KB Output is correct
16 Correct 23 ms 2176 KB Output is correct
17 Correct 488 ms 5496 KB Output is correct
18 Correct 507 ms 5496 KB Output is correct
19 Correct 471 ms 5624 KB Output is correct
20 Correct 32 ms 2176 KB Output is correct
21 Correct 24 ms 2176 KB Output is correct
22 Correct 17 ms 2048 KB Output is correct
23 Correct 15 ms 2048 KB Output is correct
24 Correct 5 ms 384 KB Output is correct
25 Correct 118 ms 5368 KB Output is correct
26 Correct 101 ms 5372 KB Output is correct
27 Correct 317 ms 5368 KB Output is correct
28 Correct 323 ms 5496 KB Output is correct
29 Correct 327 ms 5472 KB Output is correct
30 Correct 295 ms 5496 KB Output is correct
31 Correct 26 ms 2176 KB Output is correct
32 Correct 18 ms 2176 KB Output is correct
33 Correct 467 ms 4600 KB Output is correct
34 Correct 16 ms 2048 KB Output is correct
35 Correct 641 ms 5368 KB Output is correct
36 Correct 5 ms 384 KB Output is correct
37 Correct 5 ms 436 KB Output is correct
38 Correct 112 ms 5540 KB Output is correct
39 Correct 144 ms 5344 KB Output is correct
40 Correct 409 ms 5496 KB Output is correct
41 Correct 416 ms 5432 KB Output is correct
42 Correct 294 ms 5624 KB Output is correct
43 Correct 5 ms 384 KB Output is correct
44 Correct 5 ms 384 KB Output is correct
45 Correct 5 ms 384 KB Output is correct
46 Correct 5 ms 384 KB Output is correct
47 Correct 5 ms 384 KB Output is correct
48 Correct 5 ms 384 KB Output is correct
49 Correct 424 ms 5496 KB Output is correct
50 Correct 410 ms 5468 KB Output is correct
51 Correct 313 ms 5624 KB Output is correct
52 Correct 410 ms 5496 KB Output is correct
53 Correct 626 ms 5504 KB Output is correct
54 Correct 433 ms 5496 KB Output is correct
55 Correct 394 ms 5476 KB Output is correct
56 Correct 26 ms 2176 KB Output is correct
57 Correct 32 ms 2168 KB Output is correct
58 Correct 333 ms 4864 KB Output is correct
59 Correct 332 ms 4856 KB Output is correct
60 Correct 315 ms 4792 KB Output is correct
61 Correct 357 ms 4868 KB Output is correct
62 Correct 323 ms 4868 KB Output is correct
63 Correct 332 ms 4820 KB Output is correct
64 Correct 745 ms 5220 KB Output is correct
65 Correct 651 ms 6192 KB Output is correct
66 Correct 620 ms 5924 KB Output is correct
67 Correct 21 ms 3964 KB Output is correct
68 Correct 137 ms 6520 KB Output is correct
69 Correct 141 ms 6648 KB Output is correct
70 Correct 425 ms 6776 KB Output is correct
71 Correct 414 ms 6524 KB Output is correct
72 Correct 455 ms 6648 KB Output is correct
73 Correct 416 ms 6776 KB Output is correct
74 Correct 413 ms 6780 KB Output is correct