oj.uz

Submission #361247

# Submission time Handle Problem Language Result Execution time Memory
361247 2021-01-28T23:39:37 Z HoneyBadger Olympic Bus (JOI20_ho_t4) C++17
16 / 100
 73 ms 7708 KB 
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <vector>
#include <bitset>
#include <string>
#include <cstring>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <deque>
#include <utility>
#include <algorithm>
#include <random>
#include <cmath>
#include <cassert>
#include <climits>
#include <ctime>
#include <chrono>


/*
#pragma GCC optimize("Ofast")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx,avx2,tune=native")
*/


#ifdef LOCAL
    #define dbg(x) cout << #x << " : " << x << endl;
#else
    #define dbg(x)
#endif

#define int long long
#define pb push_back
#define ppb pop_back()
#define mp make_pair
#define fi(a, b) for (int i = a; i < b; i++)
#define fj(a, b) for (int j = a; j < b; j++)
#define fk(a, b) for (int k = a; k < b; k++)
#define fi1(a, b) for (int i = a - 1; i >= b; i--)
#define fj1(a, b) for (int j = a - 1; j >= b; j--)
#define fk1(a, b) for (int k = a - 1; k >= b; k--)
#define fx(x, a) for (auto& x : a)
#define rep(i, a, b) for (int i = a; i < b; ++i)
#define rep1(i, a, b) for (int i = a - 1; i >= b; --i)
#define siz(x) (int)x.size()
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

using namespace std;

template<typename T1, typename T2>inline void mine(T1 &x, const T2 &y) { if (y < x) x = y; }
template<typename T1, typename T2>inline void maxe(T1 &x, const T2 &y) { if (x < y) x = y; }

ostream& operator << (ostream &out, const vector<int> &b) {
    for (auto k : b) out << k << ' ';
    return out;
}

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef char ch;
typedef string str;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vpii;
typedef vector<vpii> vvpii;
typedef vector<ch> vch;
typedef vector<vch> vvch;
typedef vector<str> vs;



const int MOD = 1000000007;
const int INF = 1000000050;
const long long BIG = (long long)2e18 + 50;
const int MX = 200010;
const double EPS = 1e-9;


mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int n, m;
int c[MX];
int from[MX];
int to[MX];

vi bandij(int s, int ban, const vvi &g) {
	vi dist(n, BIG);
	vch used(n, 0);
	dist[s] = 0;
	for (int i = 0; i < n - 1; ++i) {
		int v = -1;
		for (int j = 0; j < n; ++j) {
			if (!used[j] && (v == -1 || dist[j] < dist[v])) {
				v = j;
			}
		}
		if (dist[v] == BIG) break;
		fx(id, g[v]) {
			if (id == ban) continue;
			mine(dist[to[id]], dist[v] + c[id]);	
		}
		used[v] = 1;
	}
	return dist;
}

pair<vvi, vi> dij(int s, const vvi & g) {
	vi dist(n, BIG);
	vch used(n, 0);
	vvpii gb(n);
	dist[s] = 0;
	for (int i = 0; i < n - 1; ++i) {
		int v = -1;
		for (int j = 0; j < n; ++j) {
			if (!used[j] && (v == -1 || dist[j] < dist[v])) {
				v = j;
			}
		}
		if (dist[v] == BIG) break;
		fx(id, g[v]) {
			if (dist[to[id]] > dist[v] + c[id]) {
				gb[to[id]].clear();
				dist[to[id]] = dist[v] + c[id];
			}
			if (dist[to[id]] == dist[v] + c[id])
				gb[to[id]].pb({from[id], id});
		}
		used[v] = 1;
	}
	vvpii gb2(n);
	for (int i = 0; i < n; ++i) {
		used[i] = 0;
		for (auto[x, id] : gb[i]) {
			gb2[x].pb({i, id});
		}
	}
	swap(gb2, gb);
	vi ord;
	function<void(int)> dfs = [&](int v) {
		used[v] = 1;
		for (auto[x, id] : gb[v]) {
			if (!used[x]) {
				dfs(x);
			}
		}
		ord.pb(v);
	};	
	dfs(s);
	reverse(all(ord));
	//dbg(ord);
	vi ways(n, 0);
	ways[s] = 1;
	fx(v, ord) {
		ways[v] %= MOD;
		for (auto[x, id] : gb[v]) {
			ways[x] += ways[v]; 
		}
	}
	//dbg(ways);
	vi bridges;
	fx(v, ord) {
		for (auto[to, id] : gb[v]) {
			if (ways[to] == ways[v]) {
				bridges.pb(id);
			}
		}
	}
	sort(all(bridges));
	vvi dists;
	fx(id, bridges) 
		dists.pb(bandij(s, id, g));
	dists.pb(dist);
	fx(x, bridges)
		x %= m;
	return mp(dists, bridges);
}


int d[MX];

int get(vi &bridges, int id) {
	auto it = lb(all(bridges), id);
	if (it == bridges.end() || *it != id)
		return bridges.size();
	return it - bridges.begin();
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

   
    cin >> n >> m;
    vvi g(n);
    vvi gc(n);
    for (int i = 0; i < m; ++i) {
    	cin >> from[i] >> to[i] >> c[i] >> d[i];
    	--from[i], --to[i];
    	from[i + m] = to[i];
    	to[i + m] = from[i];
    	c[i + m] = c[i];
    	g[from[i]].pb(i);
    	gc[from[i + m]].pb(i + m);
	}
	const int s = 0;
	const int t = n - 1;
	auto[dsv, bsv] = dij(s, g);
	auto[dvs, bvs] = dij(s, gc);
	auto[dtv, btv] = dij(t, g);
	auto[dvt, bvt] = dij(t, gc);
	/*dbg(bsv);
	fx(di, dsv) {
		dbg(di);
	}  
	dbg(bvs);
	fx(di, dvs) {
		dbg(di);
	}
	dbg(btv);
	fx(di, dtv) {
		dbg(di);
	}
	dbg(bvt);
	fx(di, dvt) {
		dbg(di);
	}
	dbg(btv);*/
	int ans = dsv.back()[t] + dtv.back()[s];
	for (int id = 0; id < m; ++id) {
		//#warning ALARM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
		//if (id != 3) continue;
		int u = from[id];
		int v = to[id];
		
		int bid = get(bsv, id);
		int st = dsv[bid][t];
		int sv = dsv[bid][v];
		bid = get(bvs, id);
		int us = dvs[bid][u];
		bid = get(btv, id);
		//dbg(bid);
		int ts = dtv[bid][s];
		int tv = dtv[bid][v];
		bid = get(bvt, id);
		int ut = dvt[bid][u];

		int cur = d[id];
		cur += min(st, sv + c[id] + ut);
		cur += min(ts, tv + c[id] + us);
		mine(ans, cur);
		/*dbg(id);
		dbg(st);
		dbg(sv);
		dbg(us);
		dbg(ts);
		dbg(tv);
		dbg(ut);
		dbg(cur);*/

	}
	cout << (ans >= BIG ? -1 : ans) << '\n';
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 620 KB Output is correct
2 Correct 3 ms 620 KB Output is correct
3 Correct 69 ms 2284 KB Output is correct
4 Correct 70 ms 2156 KB Output is correct
5 Correct 2 ms 492 KB Output is correct
6 Correct 8 ms 876 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 492 KB Output is correct
10 Correct 73 ms 2112 KB Output is correct
11 Correct 73 ms 2292 KB Output is correct
12 Correct 73 ms 2156 KB Output is correct
13 Correct 20 ms 1260 KB Output is correct
14 Correct 46 ms 1772 KB Output is correct
15 Correct 48 ms 1644 KB Output is correct
16 Correct 46 ms 1828 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 4844 KB Output is correct
2 Correct 27 ms 5612 KB Output is correct
3 Correct 26 ms 5612 KB Output is correct
4 Correct 2 ms 620 KB Output is correct
5 Correct 2 ms 492 KB Output is correct
6 Correct 2 ms 492 KB Output is correct
7 Correct 1 ms 492 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 24 ms 5612 KB Output is correct
10 Correct 25 ms 5612 KB Output is correct
11 Correct 25 ms 5612 KB Output is correct
12 Correct 25 ms 5632 KB Output is correct
13 Correct 25 ms 5612 KB Output is correct
14 Correct 25 ms 5740 KB Output is correct

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 620 KB Output is correct
2 Correct 9 ms 748 KB Output is correct
3 Correct 28 ms 5612 KB Output is correct
4 Correct 8 ms 748 KB Output is correct
5 Correct 38 ms 7708 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 29 ms 6260 KB Output is correct
9 Correct 28 ms 6320 KB Output is correct
10 Incorrect 34 ms 7688 KB Output isn't correct
11 Halted 0 ms 0 KB -

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 620 KB Output is correct
2 Correct 3 ms 620 KB Output is correct
3 Correct 69 ms 2284 KB Output is correct
4 Correct 70 ms 2156 KB Output is correct
5 Correct 2 ms 492 KB Output is correct
6 Correct 8 ms 876 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 492 KB Output is correct
10 Correct 73 ms 2112 KB Output is correct
11 Correct 73 ms 2292 KB Output is correct
12 Correct 73 ms 2156 KB Output is correct
13 Correct 20 ms 1260 KB Output is correct
14 Correct 46 ms 1772 KB Output is correct
15 Correct 48 ms 1644 KB Output is correct
16 Correct 46 ms 1828 KB Output is correct
17 Correct 24 ms 4844 KB Output is correct
18 Correct 27 ms 5612 KB Output is correct
19 Correct 26 ms 5612 KB Output is correct
20 Correct 2 ms 620 KB Output is correct
21 Correct 2 ms 492 KB Output is correct
22 Correct 2 ms 492 KB Output is correct
23 Correct 1 ms 492 KB Output is correct
24 Correct 1 ms 364 KB Output is correct
25 Correct 24 ms 5612 KB Output is correct
26 Correct 25 ms 5612 KB Output is correct
27 Correct 25 ms 5612 KB Output is correct
28 Correct 25 ms 5632 KB Output is correct
29 Correct 25 ms 5612 KB Output is correct
30 Correct 25 ms 5740 KB Output is correct
31 Correct 3 ms 620 KB Output is correct
32 Correct 9 ms 748 KB Output is correct
33 Correct 28 ms 5612 KB Output is correct
34 Correct 8 ms 748 KB Output is correct
35 Correct 38 ms 7708 KB Output is correct
36 Correct 1 ms 364 KB Output is correct
37 Correct 1 ms 364 KB Output is correct
38 Correct 29 ms 6260 KB Output is correct
39 Correct 28 ms 6320 KB Output is correct
40 Incorrect 34 ms 7688 KB Output isn't correct
41 Halted 0 ms 0 KB -