oj.uz

답안 #382220

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
382220 2021-03-26T18:13:21 Z saarang123 Commuter Pass (JOI18_commuter_pass) C++17
100 / 100
 418 ms 29352 KB 
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int mxn = 100 * 1000 + 3, inf = 1e18;
vector<array<int, 2>> g[mxn];
vector<int> par[mxn], dpchild[mxn];
int n, m;

vector<int> dij(int src) {
	vector<int> dt(n + 1, inf);
	dt[src] = 0;
	priority_queue<array<int, 2>, vector<array<int, 2>>, greater<>> pq;
	pq.push({0, src});
	while(!pq.empty()) {
		auto [wt, u] = pq.top();
		pq.pop();
		if(dt[u] != wt) continue;
		for(auto [v, w] : g[u]) {
			if(dt[u] + w < dt[v]) {
				dt[v] = dt[u] + w;
				pq.push({dt[v], v});
			}
		}
	}
	return dt;
}

vector<int> dijk(int src) {
	vector<int> dt(n + 1, inf);
	dt[src] = 0;
	priority_queue<array<int, 2>, vector<array<int, 2>>, greater<>> pq;
	pq.push({0, src});
	while(!pq.empty()) {
		auto [wt, v] = pq.top(); pq.pop();
		if(dt[v] != wt) continue;
		for(auto [u, w] : g[v]) {
			if(dt[v] + w < dt[u]) {
				dt[u] = dt[v] + w;
				pq.push({dt[u], u});
				par[u].clear(); par[u].push_back(v);
			} else if(dt[v] + w == dt[u])
				par[u].push_back(v);
		}
	}
	return dt;
}

vector<bool> reach(int src) {
	vector<bool> reachable(n + 1);
	queue<int> q; q.push(src);
    while (!q.empty()) {
        int u = q.front(); q.pop();
        if (!reachable[u]) {
            reachable[u] = true;
            for(int v : par[u]) {
                dpchild[v].push_back(u);
                q.push(v);
            }
        }
    }
	return reachable;
}

signed main() {
    std::ios::sync_with_stdio(0);
    std::cout.tie(0);
    std::cin.tie(0);
    #ifdef saarang
    freopen("/home/saarang/Documents/cp/input.txt", "r", stdin);
    freopen("/home/saarang/Documents/cp/output.txt", "w", stdout);
    #endif
    int s, t, u, v;
    cin >> n >> m >> s >> t >> u >> v;
    for(int u1, v1, w, i = 0; i < m; i++) {
    	cin >> u1 >> v1 >> w;
    	g[u1].push_back({v1, w});
    	g[v1].push_back({u1, w});
    }
    vector<int> du = dij(u), dv = dij(v), ds = dijk(s);
    vector<bool> reachable = reach(t);
    vector<int> memo(n + 1, -1), memo2(n + 1, -1);
    function<int(int v1)> dp = [&] (int v1) {
    	if(memo[v1] != -1) return memo[v1];
    	memo[v1] = dv[v1];
    	for(int u1 : par[v1])
    		memo[v1] = min(memo[v1], dp(u1));
    	return memo[v1];
    };
    function<int(int v1)> dpback = [&] (int v1) {
    	if(memo2[v1] != -1) return memo2[v1];
    	memo2[v1] = dv[v1];
    	for(int u1 : dpchild[v1])
    		memo2[v1] = min(memo2[v1], dpback(u1));
    	return memo2[v1];
    };
    int ans = du[v];
    for(int i = 1; i <= n; i++) 
    	if(reachable[i])
    		ans = min(ans, du[i] + min(dp(i), dpback(i)));
    cout << ans << '\n';
    return 0;
}

Subtask #1
16.0 / 16.0

# 결과 실행 시간 메모리 Grader output
1 Correct 328 ms 24816 KB Output is correct
2 Correct 353 ms 25440 KB Output is correct
3 Correct 381 ms 28748 KB Output is correct
4 Correct 332 ms 24524 KB Output is correct
5 Correct 364 ms 26236 KB Output is correct
6 Correct 349 ms 24464 KB Output is correct
7 Correct 370 ms 26248 KB Output is correct
8 Correct 376 ms 26232 KB Output is correct
9 Correct 330 ms 24168 KB Output is correct
10 Correct 293 ms 24272 KB Output is correct
11 Correct 161 ms 23020 KB Output is correct
12 Correct 337 ms 24224 KB Output is correct

Subtask #2
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 367 ms 27144 KB Output is correct
2 Correct 379 ms 26664 KB Output is correct
3 Correct 380 ms 26700 KB Output is correct
4 Correct 387 ms 27108 KB Output is correct
5 Correct 385 ms 26788 KB Output is correct
6 Correct 371 ms 29044 KB Output is correct
7 Correct 396 ms 29352 KB Output is correct
8 Correct 369 ms 26152 KB Output is correct
9 Correct 374 ms 26772 KB Output is correct
10 Correct 371 ms 26536 KB Output is correct
11 Correct 168 ms 24812 KB Output is correct
12 Correct 368 ms 28832 KB Output is correct

Subtask #3
24.0 / 24.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 8940 KB Output is correct
2 Correct 6 ms 7404 KB Output is correct
3 Correct 6 ms 7404 KB Output is correct
4 Correct 22 ms 10220 KB Output is correct
5 Correct 14 ms 8812 KB Output is correct
6 Correct 6 ms 7532 KB Output is correct
7 Correct 9 ms 7532 KB Output is correct
8 Correct 7 ms 7532 KB Output is correct
9 Correct 7 ms 7532 KB Output is correct
10 Correct 13 ms 8812 KB Output is correct
11 Correct 6 ms 7404 KB Output is correct
12 Correct 6 ms 7404 KB Output is correct
13 Correct 6 ms 7404 KB Output is correct
14 Correct 6 ms 7404 KB Output is correct
15 Correct 6 ms 7532 KB Output is correct

Subtask #4
45.0 / 45.0

# 결과 실행 시간 메모리 Grader output
1 Correct 328 ms 24816 KB Output is correct
2 Correct 353 ms 25440 KB Output is correct
3 Correct 381 ms 28748 KB Output is correct
4 Correct 332 ms 24524 KB Output is correct
5 Correct 364 ms 26236 KB Output is correct
6 Correct 349 ms 24464 KB Output is correct
7 Correct 370 ms 26248 KB Output is correct
8 Correct 376 ms 26232 KB Output is correct
9 Correct 330 ms 24168 KB Output is correct
10 Correct 293 ms 24272 KB Output is correct
11 Correct 161 ms 23020 KB Output is correct
12 Correct 337 ms 24224 KB Output is correct
13 Correct 367 ms 27144 KB Output is correct
14 Correct 379 ms 26664 KB Output is correct
15 Correct 380 ms 26700 KB Output is correct
16 Correct 387 ms 27108 KB Output is correct
17 Correct 385 ms 26788 KB Output is correct
18 Correct 371 ms 29044 KB Output is correct
19 Correct 396 ms 29352 KB Output is correct
20 Correct 369 ms 26152 KB Output is correct
21 Correct 374 ms 26772 KB Output is correct
22 Correct 371 ms 26536 KB Output is correct
23 Correct 168 ms 24812 KB Output is correct
24 Correct 368 ms 28832 KB Output is correct
25 Correct 14 ms 8940 KB Output is correct
26 Correct 6 ms 7404 KB Output is correct
27 Correct 6 ms 7404 KB Output is correct
28 Correct 22 ms 10220 KB Output is correct
29 Correct 14 ms 8812 KB Output is correct
30 Correct 6 ms 7532 KB Output is correct
31 Correct 9 ms 7532 KB Output is correct
32 Correct 7 ms 7532 KB Output is correct
33 Correct 7 ms 7532 KB Output is correct
34 Correct 13 ms 8812 KB Output is correct
35 Correct 6 ms 7404 KB Output is correct
36 Correct 6 ms 7404 KB Output is correct
37 Correct 6 ms 7404 KB Output is correct
38 Correct 6 ms 7404 KB Output is correct
39 Correct 6 ms 7532 KB Output is correct
40 Correct 328 ms 23504 KB Output is correct
41 Correct 332 ms 24196 KB Output is correct
42 Correct 327 ms 24248 KB Output is correct
43 Correct 186 ms 25324 KB Output is correct
44 Correct 167 ms 25452 KB Output is correct
45 Correct 418 ms 28328 KB Output is correct
46 Correct 412 ms 28348 KB Output is correct
47 Correct 353 ms 24800 KB Output is correct
48 Correct 193 ms 23916 KB Output is correct
49 Correct 291 ms 24592 KB Output is correct
50 Correct 404 ms 27472 KB Output is correct
51 Correct 417 ms 28488 KB Output is correct