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Submission #469280

# Submission time Handle Problem Language Result Execution time Memory
469280 2021-08-31T10:46:16 Z sinamhdv LOSTIKS (INOI20_lostiks) C++11
100 / 100
 1239 ms 286664 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int mod = 1000 * 1000 * 1000 + 7;
const int INF = 1e9 + 100;
const ll LINF = 1e18 + 100;

#ifdef DEBUG
#define dbg(x) cout << #x << " = " << (x) << endl << flush;
#define dbgr(s, f) { cout << #s << ": "; for (auto _ = (s); _ != (f); _++) cout << *_ << ' '; cout << endl << flush; }
#else
#define dbg(x) ;
#define dbgr(s, f) ;
#endif
#define fast_io ios::sync_with_stdio(0); cin.tie(0);
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define fr first
#define sc second
#define endl '\n'

const int MAXN = 1000010;
const int MAXE = 22;
const int LOGN = 23;

int n, s, t, m;
int ef[MAXN], eto[MAXN], ky[MAXN], kind[MAXN];
vector<int> adj[MAXN];
int lpar[LOGN][MAXN];
int h[MAXN];
int pth[MAXN];
int lck[MAXE];
int dp[1 << 20][22];
int inp[MAXE];
int cost[MAXE][MAXE];
int tot;

void dfs(int v)
{
	for (int e : adj[v])
	{
		int u = ef[e] ^ eto[e] ^ v;
		if (u == lpar[0][v]) continue;
		lpar[0][u] = v;
		h[u] = h[v] + 1;
		pth[u] = pth[v] | (ky[e] ? (1 << kind[e]) : 0);
		dfs(u);
	}
}

void bkdfs(int v)
{
	tot |= (1 << v);
	FOR(i, 0, m) if ((inp[v] >> i & 1) && !(tot >> i & 1)) bkdfs(i);
}

inline int getpar(int x, int d)
{
	FOR(i, 0, LOGN) if (d >> i & 1) x = lpar[i][x];
	return x;
}

inline int getlca(int x, int y)
{
	if (h[x] > h[y]) swap(x, y);
	y = getpar(y, h[y] - h[x]);
	if (x == y) return x;
	for (int i = LOGN - 1; i >= 0; i--)
	{
		if (lpar[i][x] != lpar[i][y])
		{
			x = lpar[i][x];
			y = lpar[i][y];
		}
	}
	return lpar[0][x];
}

int32_t main(void)
{
	fast_io;
	cin >> n >> s >> t;
	FOR(i, 0, n - 1)
	{
		cin >> ef[i] >> eto[i] >> ky[i];
		adj[ef[i]].pb(i);
		adj[eto[i]].pb(i);
		if (ky[i])
		{
			lck[m] = i;
			kind[i] = m;
			m++;
		}
	}

	dbg(m);

	dfs(s);

	dbgr(pth + 1, pth + n + 1);
	if (pth[t] == 0)
	{
		return cout << h[t] << endl, 0;
	}

	FOR(i, 0, n - 1) if (h[ef[i]] > h[eto[i]]) swap(ef[i], eto[i]);

	FOR(i, 1, LOGN) FOR(j, 1, n + 1) lpar[i][j] = lpar[i - 1][lpar[i - 1][j]];

	FOR(i, 0, m)
	{
		int e = lck[i];
		inp[i] = (pth[ef[e]] | pth[ky[e]]);
	}

	FOR(i, 0, m) FOR(j, 0, m) if (i != j)
	{
		int x = ef[lck[i]];
		int y = ky[lck[j]];
		int z = ef[lck[j]];
		cost[i][j] = h[x] + h[y] - 2 * h[getlca(x, y)] + h[y] + h[z] - 2 * h[getlca(y, z)];

//		cout << i << ' ' << j << ' ' << cost[i][j] << endl;
	}

	dbgr(h + 1, h + n + 1);
	dbgr(pth + 1, pth + n + 1);
	dbgr(lck, lck + m);
	dbgr(inp, inp + m);

	FOR(mask, 1, 1 << m) fill(dp[mask], dp[mask] + MAXE, INF);

	FOR(mask, 1, 1 << m)
	{
		if (__builtin_popcount(mask) == 1)
		{
			int v = __lg(mask);
			if (!(inp[v] & mask)) dp[mask][v] = 0;
			continue;
		}
		FOR(v, 0, m)
		{
			if ((mask >> v & 1) && (inp[v] & mask) == 0)
			{
				int sub = mask ^ (1 << v);
				FOR(x, 0, m) if (sub >> x & 1)
				{
					dp[mask][v] = min(dp[mask][v], dp[sub][x] + cost[v][x]);
				}
			}
		}
	}

//	FOR(mask, 0, 1 << m) FOR(v, 0, m) cout << v << ' ' << mask << ' ' << dp[mask][v] << endl;

	int laste = -1;
	FOR(i, 0, m) if (pth[t] >> i & 1) if (laste == -1 || h[ef[lck[i]]] > h[ef[lck[laste]]]) laste = i;

	bkdfs(laste);
	int ans = INF;
	FOR(v, 0, m)
	{
		int cs = h[ky[lck[v]]] + h[ky[lck[v]]] + h[ef[lck[v]]] - 2 * h[getlca(ky[lck[v]], ef[lck[v]])];
		ans = min(ans, cs + dp[tot][v]);
	}

	if (ans >= INF) return cout << "-1\n", 0;
	ans += h[t] - h[ef[lck[laste]]];

	cout << ans << endl;

	return 0;
}

Subtask #1
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 24012 KB Output is correct
2 Correct 13 ms 24036 KB Output is correct
3 Correct 70 ms 38332 KB Output is correct
4 Correct 73 ms 38360 KB Output is correct
5 Correct 73 ms 38444 KB Output is correct
6 Correct 72 ms 38340 KB Output is correct
7 Correct 72 ms 38444 KB Output is correct
8 Correct 74 ms 38408 KB Output is correct
9 Correct 74 ms 38604 KB Output is correct
10 Correct 71 ms 38420 KB Output is correct
11 Correct 77 ms 38504 KB Output is correct
12 Correct 74 ms 40432 KB Output is correct
13 Correct 69 ms 39988 KB Output is correct
14 Correct 66 ms 39520 KB Output is correct
15 Correct 81 ms 40508 KB Output is correct
16 Correct 71 ms 41276 KB Output is correct
17 Correct 67 ms 41268 KB Output is correct
18 Correct 69 ms 41796 KB Output is correct
19 Correct 77 ms 45832 KB Output is correct
20 Correct 74 ms 45668 KB Output is correct
21 Correct 72 ms 45380 KB Output is correct
22 Correct 13 ms 24028 KB Output is correct
23 Correct 15 ms 23992 KB Output is correct
24 Correct 14 ms 24012 KB Output is correct
25 Correct 14 ms 24072 KB Output is correct
26 Correct 14 ms 23756 KB Output is correct

Subtask #2
36.0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 24012 KB Output is correct
2 Correct 13 ms 24012 KB Output is correct
3 Correct 13 ms 24040 KB Output is correct
4 Correct 14 ms 24140 KB Output is correct
5 Correct 167 ms 70108 KB Output is correct
6 Correct 142 ms 70136 KB Output is correct
7 Correct 195 ms 70084 KB Output is correct
8 Correct 150 ms 70124 KB Output is correct
9 Correct 183 ms 70192 KB Output is correct
10 Correct 118 ms 70212 KB Output is correct
11 Correct 110 ms 70220 KB Output is correct
12 Correct 109 ms 70212 KB Output is correct
13 Correct 124 ms 70212 KB Output is correct
14 Correct 110 ms 70212 KB Output is correct
15 Correct 148 ms 70220 KB Output is correct
16 Correct 182 ms 70212 KB Output is correct
17 Correct 157 ms 70184 KB Output is correct
18 Correct 109 ms 70380 KB Output is correct
19 Correct 111 ms 70292 KB Output is correct
20 Correct 128 ms 70380 KB Output is correct
21 Correct 109 ms 70348 KB Output is correct
22 Correct 118 ms 70724 KB Output is correct
23 Correct 112 ms 70676 KB Output is correct
24 Correct 109 ms 70720 KB Output is correct
25 Correct 820 ms 114296 KB Output is correct

Subtask #3
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 24012 KB Output is correct
2 Correct 13 ms 24036 KB Output is correct
3 Correct 70 ms 38332 KB Output is correct
4 Correct 73 ms 38360 KB Output is correct
5 Correct 73 ms 38444 KB Output is correct
6 Correct 72 ms 38340 KB Output is correct
7 Correct 72 ms 38444 KB Output is correct
8 Correct 74 ms 38408 KB Output is correct
9 Correct 74 ms 38604 KB Output is correct
10 Correct 71 ms 38420 KB Output is correct
11 Correct 77 ms 38504 KB Output is correct
12 Correct 74 ms 40432 KB Output is correct
13 Correct 69 ms 39988 KB Output is correct
14 Correct 66 ms 39520 KB Output is correct
15 Correct 81 ms 40508 KB Output is correct
16 Correct 71 ms 41276 KB Output is correct
17 Correct 67 ms 41268 KB Output is correct
18 Correct 69 ms 41796 KB Output is correct
19 Correct 77 ms 45832 KB Output is correct
20 Correct 74 ms 45668 KB Output is correct
21 Correct 72 ms 45380 KB Output is correct
22 Correct 13 ms 24028 KB Output is correct
23 Correct 15 ms 23992 KB Output is correct
24 Correct 14 ms 24012 KB Output is correct
25 Correct 14 ms 24072 KB Output is correct
26 Correct 14 ms 23756 KB Output is correct
27 Correct 13 ms 24012 KB Output is correct
28 Correct 13 ms 24012 KB Output is correct
29 Correct 13 ms 24040 KB Output is correct
30 Correct 14 ms 24140 KB Output is correct
31 Correct 167 ms 70108 KB Output is correct
32 Correct 142 ms 70136 KB Output is correct
33 Correct 195 ms 70084 KB Output is correct
34 Correct 150 ms 70124 KB Output is correct
35 Correct 183 ms 70192 KB Output is correct
36 Correct 118 ms 70212 KB Output is correct
37 Correct 110 ms 70220 KB Output is correct
38 Correct 109 ms 70212 KB Output is correct
39 Correct 124 ms 70212 KB Output is correct
40 Correct 110 ms 70212 KB Output is correct
41 Correct 148 ms 70220 KB Output is correct
42 Correct 182 ms 70212 KB Output is correct
43 Correct 157 ms 70184 KB Output is correct
44 Correct 109 ms 70380 KB Output is correct
45 Correct 111 ms 70292 KB Output is correct
46 Correct 128 ms 70380 KB Output is correct
47 Correct 109 ms 70348 KB Output is correct
48 Correct 118 ms 70724 KB Output is correct
49 Correct 112 ms 70676 KB Output is correct
50 Correct 109 ms 70720 KB Output is correct
51 Correct 820 ms 114296 KB Output is correct
52 Correct 1190 ms 172184 KB Output is correct
53 Correct 1192 ms 172380 KB Output is correct
54 Correct 1154 ms 170028 KB Output is correct
55 Correct 1191 ms 169440 KB Output is correct
56 Correct 1222 ms 170544 KB Output is correct
57 Correct 1166 ms 172132 KB Output is correct
58 Correct 14 ms 24012 KB Output is correct
59 Correct 13 ms 24012 KB Output is correct
60 Correct 13 ms 24016 KB Output is correct
61 Correct 1184 ms 172340 KB Output is correct
62 Correct 1207 ms 180528 KB Output is correct
63 Correct 1239 ms 174952 KB Output is correct
64 Correct 95 ms 41044 KB Output is correct
65 Correct 86 ms 41332 KB Output is correct
66 Correct 1209 ms 172424 KB Output is correct
67 Correct 1173 ms 172064 KB Output is correct
68 Correct 1084 ms 212644 KB Output is correct
69 Correct 1058 ms 213188 KB Output is correct
70 Correct 1138 ms 212480 KB Output is correct
71 Correct 1130 ms 212420 KB Output is correct
72 Correct 1062 ms 212420 KB Output is correct
73 Correct 1010 ms 214044 KB Output is correct
74 Correct 1151 ms 214848 KB Output is correct
75 Correct 1041 ms 214496 KB Output is correct
76 Correct 1027 ms 215436 KB Output is correct
77 Correct 1048 ms 214188 KB Output is correct
78 Correct 1012 ms 222084 KB Output is correct
79 Correct 1018 ms 221568 KB Output is correct
80 Correct 996 ms 220028 KB Output is correct
81 Correct 937 ms 236528 KB Output is correct
82 Correct 984 ms 238160 KB Output is correct
83 Correct 980 ms 237880 KB Output is correct
84 Correct 1016 ms 248952 KB Output is correct
85 Correct 1051 ms 286664 KB Output is correct
86 Correct 997 ms 285384 KB Output is correct
87 Correct 983 ms 285648 KB Output is correct