Submission #539271

# Submission time Handle Problem Language Result Execution time Memory
539271 2022-03-18T15:59:11 Z nafis_shifat Olympic Bus (JOI20_ho_t4) C++14
100 / 100
390 ms 8080 KB
#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
using namespace std;
const int mxn=2e5+5;
const ll INF=1e15;
int n,m;
int l[mxn], r[mxn];
ll c[mxn], d[mxn];
vector<int> adj[mxn];

bool blocked[mxn] = {};
bool used[mxn] = {};
void dijkstra(int s, vector<ll> &d, vector<int> & p) {
    
    d.resize(n + 1);
    p.resize(n + 1);

    for(int i = 1; i <= n; i++) {
    	d[i] = INF;
    	p[i] = -1;
    }
    vector<bool> u(n, false);

    d[s] = 0;
    for(int i = 1; i <= n; i++) {
        int v = -1;
        for (int j = 1; j <= n; j++) {
            if (!u[j] && (v == -1 || d[j] < d[v]))
                v = j;
        }

        if(d[v] == INF)
            break;

        u[v] = true;
        for (auto edge : adj[v]) {
        	if(blocked[edge]) continue;
            int to = r[edge];
            ll len = c[edge];

            if (d[v] + len < d[to]) {
                d[to] = d[v] + len;
                p[to] = edge;
            }
        }
    }
}



int main() {
	cin >> n >> m;

	ll w[n + 1][n + 1];
	for(int i = 1; i <= n; i++) for(int j = 1; j <= n; j++) {
		if(i == j) w[i][j] = 0;
		else w[i][j] = INF;
	}

	for(int i = 1; i <= m; i++) {
		scanf("%d %d %lld %lld",&l[i],&r[i],&c[i],&d[i]);
		adj[l[i]].push_back(i);
		w[l[i]][r[i]] = min(w[l[i]][r[i]], c[i]);
	}

	for(int k = 1; k <= n; k++) {
		for(int i = 1; i <= n; i++) {
			for(int j = 1; j <= n; j++) {
				w[i][j] = min(w[i][j], w[i][k] + w[k][j]);
			}
		}
	}



	ll ans = w[1][n] + w[n][1];
	
	int source = 1;
	int target = n;
	


	vector<ll> dist1, dist2;
	vector<int> last1, last2;
	vector<int> sedg;

	dijkstra(source, dist1, last1);
	dijkstra(target, dist2, last2);




	if(dist1[target] < INF) {
		int nd = target;
		while(nd != source) {    
			used[last1[nd]] = true;
			sedg.push_back(last1[nd]);
			nd = l[last1[nd]];
		}

	}


	if(dist2[source] < INF) {
		int nd = source;
		while(nd != target) {    
			used[last2[nd]] = true;
			sedg.push_back(last2[nd]);
			nd = l[last2[nd]];
		}

	}
	

	
	
	
	




	for(int i = 1; i <= m; i++) {
		if(used[i]) continue;
		ans = min(ans, w[source][target] + w[target][r[i]] + d[i] + c[i] + w[l[i]][source]);
		ans = min(ans, d[i] + w[source][r[i]] + c[i] + w[l[i]][target] + w[target][source]);
		ans = min(ans, d[i] + w[source][r[i]] + c[i] + w[l[i]][target] + w[target][r[i]] + c[i] + w[l[i]][source]);
	}


	for(int i : sedg) {
		blocked[i] = true;
		vector<int> cl;
		l[m + 1] = r[i];
		r[m + 1] = l[i];
		c[m + 1] = c[i];

		adj[l[m + 1]].push_back(m + 1);

		dijkstra(source, dist1, cl);
		dijkstra(target, dist2, cl);
		ans = min(ans, d[i] + dist1[target] + dist2[source]);
		blocked[i] = false;
		adj[l[m + 1]].pop_back();
	}

	if(ans >= INF) cout<<-1<<endl;
	else cout<<ans<<endl;








	
}

Compilation message

ho_t4.cpp: In function 'int main()':
ho_t4.cpp:62:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |   scanf("%d %d %lld %lld",&l[i],&r[i],&c[i],&d[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 16 ms 5332 KB Output is correct
2 Correct 12 ms 5348 KB Output is correct
3 Correct 14 ms 5376 KB Output is correct
4 Correct 15 ms 5332 KB Output is correct
5 Correct 4 ms 4948 KB Output is correct
6 Correct 11 ms 5348 KB Output is correct
7 Correct 4 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 5 ms 4948 KB Output is correct
10 Correct 93 ms 5368 KB Output is correct
11 Correct 95 ms 5372 KB Output is correct
12 Correct 92 ms 5368 KB Output is correct
13 Correct 12 ms 5332 KB Output is correct
14 Correct 14 ms 5332 KB Output is correct
15 Correct 13 ms 5332 KB Output is correct
16 Correct 15 ms 5352 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 39 ms 6868 KB Output is correct
2 Correct 40 ms 7812 KB Output is correct
3 Correct 40 ms 8052 KB Output is correct
4 Correct 20 ms 5436 KB Output is correct
5 Correct 15 ms 5384 KB Output is correct
6 Correct 17 ms 5332 KB Output is correct
7 Correct 12 ms 5268 KB Output is correct
8 Correct 5 ms 4948 KB Output is correct
9 Correct 36 ms 7940 KB Output is correct
10 Correct 34 ms 8016 KB Output is correct
11 Correct 39 ms 7968 KB Output is correct
12 Correct 41 ms 8060 KB Output is correct
13 Correct 42 ms 8008 KB Output is correct
14 Correct 46 ms 8080 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 22 ms 5332 KB Output is correct
2 Correct 16 ms 5248 KB Output is correct
3 Correct 33 ms 6504 KB Output is correct
4 Correct 12 ms 5360 KB Output is correct
5 Correct 36 ms 7172 KB Output is correct
6 Correct 4 ms 4948 KB Output is correct
7 Correct 4 ms 4948 KB Output is correct
8 Correct 36 ms 7188 KB Output is correct
9 Correct 34 ms 7168 KB Output is correct
10 Correct 34 ms 7188 KB Output is correct
11 Correct 35 ms 7180 KB Output is correct
12 Correct 36 ms 7184 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 4948 KB Output is correct
15 Correct 3 ms 5008 KB Output is correct
16 Correct 4 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 4 ms 4980 KB Output is correct
19 Correct 36 ms 7784 KB Output is correct
20 Correct 36 ms 7724 KB Output is correct
21 Correct 41 ms 7776 KB Output is correct
22 Correct 36 ms 7768 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 16 ms 5332 KB Output is correct
2 Correct 12 ms 5348 KB Output is correct
3 Correct 14 ms 5376 KB Output is correct
4 Correct 15 ms 5332 KB Output is correct
5 Correct 4 ms 4948 KB Output is correct
6 Correct 11 ms 5348 KB Output is correct
7 Correct 4 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 5 ms 4948 KB Output is correct
10 Correct 93 ms 5368 KB Output is correct
11 Correct 95 ms 5372 KB Output is correct
12 Correct 92 ms 5368 KB Output is correct
13 Correct 12 ms 5332 KB Output is correct
14 Correct 14 ms 5332 KB Output is correct
15 Correct 13 ms 5332 KB Output is correct
16 Correct 15 ms 5352 KB Output is correct
17 Correct 39 ms 6868 KB Output is correct
18 Correct 40 ms 7812 KB Output is correct
19 Correct 40 ms 8052 KB Output is correct
20 Correct 20 ms 5436 KB Output is correct
21 Correct 15 ms 5384 KB Output is correct
22 Correct 17 ms 5332 KB Output is correct
23 Correct 12 ms 5268 KB Output is correct
24 Correct 5 ms 4948 KB Output is correct
25 Correct 36 ms 7940 KB Output is correct
26 Correct 34 ms 8016 KB Output is correct
27 Correct 39 ms 7968 KB Output is correct
28 Correct 41 ms 8060 KB Output is correct
29 Correct 42 ms 8008 KB Output is correct
30 Correct 46 ms 8080 KB Output is correct
31 Correct 22 ms 5332 KB Output is correct
32 Correct 16 ms 5248 KB Output is correct
33 Correct 33 ms 6504 KB Output is correct
34 Correct 12 ms 5360 KB Output is correct
35 Correct 36 ms 7172 KB Output is correct
36 Correct 4 ms 4948 KB Output is correct
37 Correct 4 ms 4948 KB Output is correct
38 Correct 36 ms 7188 KB Output is correct
39 Correct 34 ms 7168 KB Output is correct
40 Correct 34 ms 7188 KB Output is correct
41 Correct 35 ms 7180 KB Output is correct
42 Correct 36 ms 7184 KB Output is correct
43 Correct 3 ms 4948 KB Output is correct
44 Correct 3 ms 4948 KB Output is correct
45 Correct 3 ms 5008 KB Output is correct
46 Correct 4 ms 4948 KB Output is correct
47 Correct 3 ms 4948 KB Output is correct
48 Correct 4 ms 4980 KB Output is correct
49 Correct 36 ms 7784 KB Output is correct
50 Correct 36 ms 7724 KB Output is correct
51 Correct 41 ms 7776 KB Output is correct
52 Correct 36 ms 7768 KB Output is correct
53 Correct 54 ms 7876 KB Output is correct
54 Correct 44 ms 7764 KB Output is correct
55 Correct 43 ms 7764 KB Output is correct
56 Correct 15 ms 5400 KB Output is correct
57 Correct 19 ms 5332 KB Output is correct
58 Correct 211 ms 7412 KB Output is correct
59 Correct 248 ms 7408 KB Output is correct
60 Correct 213 ms 7400 KB Output is correct
61 Correct 175 ms 7436 KB Output is correct
62 Correct 272 ms 7372 KB Output is correct
63 Correct 260 ms 7408 KB Output is correct
64 Correct 390 ms 7472 KB Output is correct
65 Correct 376 ms 7372 KB Output is correct
66 Correct 349 ms 7464 KB Output is correct
67 Correct 20 ms 6968 KB Output is correct
68 Correct 42 ms 7956 KB Output is correct
69 Correct 37 ms 7916 KB Output is correct
70 Correct 46 ms 8008 KB Output is correct
71 Correct 37 ms 8012 KB Output is correct
72 Correct 46 ms 7984 KB Output is correct
73 Correct 40 ms 8012 KB Output is correct
74 Correct 44 ms 7972 KB Output is correct