Submission #274144

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
274144	2020-08-19T08:45:43 Z	임성재(#5106)	Mountains and Valleys (CCO20_day1problem3)	C++17	2 / 25	122 ms	110972 KB

Main

#include<bits/stdc++.h>
using namespace std;

#define fast ios::sync_with_stdio(false); cin.tie(0);
#define fi first
#define se second
#define em emplace
#define eb emplace_back
#define mp make_pair
#define all(v) (v).begin(), (v).end()

typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
const int inf = 1e9;
const ll INF = 1e18;

int n, m;
vector<pair<pii, int>> e;
vector<int> g[500010];
int dis[5010][5010];
int d[5010];
int sp[5010][21];

int lca(int a, int b) {
	if(d[a] > d[b]) swap(a, b);

	for(int i=20; i>=0; i--) {
		if(d[b] - d[a] >= (1<<i)) b = sp[b][i];
	}

	if(a == b) return a;

	for(int i=20; i>=0; i--) {
		if(sp[a][i] != sp[b][i]) {
			a = sp[a][i];
			b = sp[b][i];
		}
	}

	return sp[a][0];
}

int dist(int a, int b) {
	if(dis[a][b] >= 0) return dis[a][b];

	return dis[a][b] = d[a] + d[b] - 2 * d[lca(a, b)];
}

pii uni(pii x, pii y) {
	pii ret = x;

	if(dist(y.fi, y.se) > dist(ret.fi, ret.se)) ret = y;
	if(dist(x.fi, y.fi) > dist(ret.fi, ret.se)) ret = mp(x.fi, y.fi);
	if(dist(x.fi, y.se) > dist(ret.fi, ret.se)) ret = mp(x.fi, y.se);
	if(dist(x.se, y.fi) > dist(ret.fi, ret.se)) ret = mp(x.se, y.fi);
	if(dist(x.se, y.se) > dist(ret.fi, ret.se)) ret = mp(x.se, y.se);

	return ret;
}

void dfs(int x) {
	for(int i=1; i<=20; i++)
		sp[x][i] = sp[sp[x][i-1]][i-1];

	for(auto i : g[x]) {
		if(i == sp[x][0]) continue;

		d[i] = d[x] + 1;
		sp[i][0] = x;
		dfs(i);
	}
}

pii f(int r, int x, int y) {
	queue<int> q;
	int dp[5010] = {};

	dp[r] = 1;
	q.em(r);

	while(q.size()) {
		int c = q.front();
		q.pop();

		for(auto i : g[c]) {
			if(dp[i] || i == x || i == y) continue;

			dp[i] = dp[c] + 1;
			q.em(i);
		}
	}

	int mx = -1, mxi=0;
	for(int i=0; i<n; i++) {
		if(dp[i]-1 > mx) {
			mx = dp[i] - 1;
			mxi = i;
		}
	}

	return mp(mx, mxi);
}

pii D(int x, int p, int q) {
	int u = f(x, p, q).se;
	int v = f(u, p, q).se;

	return mp(u, v);
}

int main() {
	fast;

	cin >> n >> m;

	for(int i=0; i<n; i++)
		for(int j=0; j<n; j++)
			dis[i][j] = -1;
	
	for(int i=0; i<m; i++) {
		int x, y, w;
		cin >> x >> y >> w;

		if(w == 1) {
			g[x].eb(y);
			g[y].eb(x);
		}
		else {
			e.eb(mp(x, y), w);
		}
	}

	dfs(0);

	int ans = 2 * n - 2 - dist(D(0, -1, -1).fi, D(0, -1, -1).se);

	/*for(auto i : e) {
		int x = i.fi.fi;
		int y = i.fi.se;
		int w = i.se;

		for(int i=x; i; i = sp[i][0]) {
			int u, v, l;

			tie(u, v) = D(i, sp[i][0], -1);
			l = max(dist(u, x), dist(v, x));

			tie(u, v) = D(sp[i][0], i, -1);
			l += max(dist(u, y), dist(v, y));

			//ans = min(ans, 2 * n - 4 + w - l);
		}

		for(int i=y; i; i = sp[i][0]) {
			int u, v, l;
			
			tie(u, v) = D(sp[i][0], i, -1);
			l = max(dist(u, x), dist(v, x));
			//cout << u << " " << v << " " << l << endl;

			tie(u, v) = D(i, sp[i][0], -1);
			l += max(dist(u, y), dist(v, y));
			//cout << u << " " << v << " " << l << endl;

			//cout << x << " " << y << " " << 2 * n - 4 + w - l << " " << l << endl;

			//ans = min(ans, 2 * n - 4 + w - l);
		}
	}*/

	cout << ans;
}

Subtask #1
0.0 / 1.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #2
0.0 / 2.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #3
2.0 / 2.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	82 ms	110968 KB	Output is correct
2	Correct	113 ms	110972 KB	Output is correct
3	Correct	91 ms	110840 KB	Output is correct
4	Correct	74 ms	110840 KB	Output is correct
5	Correct	79 ms	110840 KB	Output is correct
6	Correct	74 ms	110840 KB	Output is correct
7	Correct	74 ms	110968 KB	Output is correct
8	Correct	74 ms	110844 KB	Output is correct
9	Correct	74 ms	110968 KB	Output is correct
10	Correct	73 ms	110840 KB	Output is correct
11	Correct	73 ms	110840 KB	Output is correct
12	Correct	122 ms	110608 KB	Output is correct
13	Correct	105 ms	110840 KB	Output is correct
14	Correct	83 ms	110792 KB	Output is correct

Subtask #4
0.0 / 6.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #5
0.0 / 2.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #6
0.0 / 3.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #7
0.0 / 5.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Subtask #8
0.0 / 4.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	11 ms	12160 KB	Output is correct
2	Correct	8 ms	12084 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12160 KB	Output is correct
5	Correct	8 ms	12160 KB	Output is correct
6	Correct	8 ms	12160 KB	Output is correct
7	Correct	10 ms	12160 KB	Output is correct
8	Correct	11 ms	12160 KB	Output is correct
9	Correct	8 ms	12160 KB	Output is correct
10	Correct	16 ms	12160 KB	Output is correct
11	Incorrect	9 ms	12160 KB	Output isn't correct
12	Halted	0 ms	0 KB	-

Submission #274144

Compilation message