oj.uz

Submission #249943

# Submission time Handle Problem Language Result Execution time Memory
249943 2020-07-16T14:37:10 Z mieszko11b Dynamic Diameter (CEOI19_diameter) C++14
100 / 100
 2079 ms 36600 KB 
#include <bits/stdc++.h>

using namespace std;

#define X first
#define Y second

using ll = long long;
using ii = pair<int, int>;
using pll = pair<ll, ll>;

struct SegmentSegmentTree {
	int lv;
	vector<pll> d;
	vector<ll> ins;
	
	//1..n
	SegmentSegmentTree(int n) {
		lv = 2;
		while(lv < n + 2)
			lv *= 2;
		d.resize(2 * lv + 3, {-1e18, 0});
		ins.resize(2 * lv + 3);
		for(int i = 1 ; i <= lv ; i++)
			d[lv + i - 1].Y = i;
	}
	
	void initv(int i, ll x) {
		d[lv + i - 1].X = x;
	}
	
	void process_init() {
		for(int i = lv - 1 ; i >= 1 ; i--)
			d[i] = max(d[2 * i], d[2 * i + 1]);
	}
	
	void insert(int a, int b, int l, int r, int w, ll x) {
		if(a > r || b < l || l > r)
			return ;
		if(a <= l && r <= b) {
			ins[w] += x;
			d[w].X += x;
			return; 
		}
		
		insert(a, b, l, (l + r) / 2, 2 * w, x);
		insert(a, b, (l + r) / 2 + 1, r, 2 * w + 1, x);
		d[w] = max(d[2 * w], d[2 * w + 1]);
		d[w].X += ins[w];
	}
	
	void insert(int a, int b, ll x) {
		insert(a, b, 1, lv, 1, x);
	}
	
	pll query(int a, int b, int l, int r, int w) {
		if(a > r || b < l || l > r)
			return {-1e18, 0};
		if(a <= l && r <= b)
			return d[w];
		
		pll p1 = query(a, b, l, (l + r) / 2, 2 * w);
		pll p2 = query(a, b, (l + r) / 2 + 1, r, 2 * w + 1);
		p1 = max(p1, p2);
		p1.X += ins[w];
		return p1;
	}
	
	pll query(int a, int b) {
		return query(a, b, 1, lv, 1);
	}
};

int n, q;
ll w;
vector<pll> G[100007];
ii E[100007];
ll ecost[100007];
int p[100007], sz[100007];
int in[100007], out[100007];
int rein[100007];
int nxt_num = 1;
int first[100007];
SegmentSegmentTree paths(100007);
SegmentSegmentTree subtrees(100007);

void dfs(int w) {
	sz[w] = 1;
	for(auto u : G[w]) {
		if(u.X != p[w]) {
			p[u.X] = w;
			dfs(u.X);
			sz[w] += sz[u.X];
		}
	}
}

ll dfs2(int w, ll dist) {
	for(auto &u : G[w])
		if(sz[u.X] > sz[G[w][0].X])	
			swap(u, G[w][0]);
			
	in[w] = out[w] = nxt_num++;
	rein[in[w]] = w;
	
	subtrees.initv(in[w], dist);

	ll maxdist = dist, maxall = dist;
	for(auto u : G[w]) {
		if(u == G[w][0])
			first[u.X] = first[w];
		else
			first[u.X] = u.X;
		if(u != G[w][0])
			maxdist = max(maxdist, dfs2(u.X, dist + u.Y));
		else
			maxall = max(maxall, dfs2(u.X, dist + u.Y));
		out[w] = out[u.X];
	}
	
	//~ cout << w << " " << maxdist << endl;
	
	maxall = max(maxall, maxdist);
	paths.initv(in[w], maxdist - 2LL * dist);
	
	return maxall;
}

ll longest_path() {
	auto q = subtrees.query(1, n);
	int w = rein[q.Y], pre = 0;
	ll dw = q.X;

	//~ cout << dw << " " << w << endl;

	ll res = 0;
	while(w) {
		if(!pre || first[pre] == first[w]) {
			res = max(res, paths.query(in[first[w]], in[w]).X + dw);
			//~ cout << in[first[w]] << " " << in[w] << " " << w << " " << res << " " << paths.query(in[first[w]], in[w]).X << endl;
			pre = first[w];
			w = p[first[w]];
		} else {
			ll pdist = subtrees.query(in[w], in[w]).X;
			res = max(res, subtrees.query(in[w], in[pre] - 1).X + dw - 2LL * pdist);
									//~ cout << w << " " << pre << " " << pdist << " " << dw << " " << res << endl;
			res = max(res, subtrees.query(out[pre] + 1, out[w]).X + dw - 2LL * pdist);
						//~ cout << w << " " << pre << " " << pdist << " " << dw << " " << res << endl;
			pre = w;
			w = p[w];
		}
	}
	
	
	return res;
}

void change_edge(int e, ll x) {
	//~ cout << e << " " << x << endl;
	
	int w = E[e].X;
	int u = E[e].Y;
	if(in[w] > in[u])
		swap(w, u);
		
	ll delta = x - ecost[e];
	ecost[e] = x;
		
	paths.insert(in[u], out[u], -delta);
	subtrees.insert(in[u], out[u], delta);
	
	w = p[first[u]];
	
	//~ cout << w << " " << u << endl;
	
	while(w) {
		//~ cout << w << endl;
		ll actv = paths.query(in[w], in[w]).X;
		ll pdist = subtrees.query(in[w], in[w]).X;
		ll newv = subtrees.query(out[G[w][0].X] + 1, out[w]).X - 2LL * pdist;
		
		//~ cout << actv << " " << newv << endl;
		
		paths.insert(in[w], in[w], newv - actv);
		w = p[first[w]];
	}
}

int main() {
	scanf("%d%d%lld", &n, &q, &w);
	for(int i = 1 ; i < n ; i++) {
		int a, b;
		ll c;
		scanf("%d%d%lld", &a, &b, &c);
		G[a].emplace_back(b, c);
		G[b].emplace_back(a, c);
		ecost[i] = c;
		E[i] = {a, b};
	}
	
	dfs(1);
	for(int i = 1 ; i <= n ; i++) {
		for(int j = 0 ; j < G[i].size() ; j++) {
			if(G[i][j].X == p[i]) {
				G[i].erase(G[i].begin() + j);
				break;
			}
		}
	}
	
	first[1] = 1;
	dfs2(1, 0);
	subtrees.process_init();
	paths.process_init();

	//~ for(int i = 1 ; i <= n ; i++)
		//~ cout << i << " "<< first[i] << endl;

	//~ cout << longest_path() << endl;

	//~ cout << paths.query(1, 1).X << endl;

		
		//~ for(int i = 1 ; i <= n ; i++)
			//~ cout << i << " " << in[i] << " " << paths.query(in[i], in[i]).X << " " << paths.query(in[i], in[i]).Y << endl;

	ll last = 0;
	while(q--) {
		ll d, e;
		scanf("%lld%lld", &d, &e);
		d = (d + last) % (n - 1);
		e = (e + last) % w;
		
		change_edge(d + 1, e);
	
		
		//~ for(int i = 1 ; i <= n ; i++)
			//~ cout << i << " " << in[i] << " " << paths.query(in[i], in[i]).X << " " << paths.query(in[i], in[i]).Y << endl;
		
		printf("%lld\n", last = longest_path());
	}
	
	return 0;
}

Compilation message

diameter.cpp: In function 'int main()':
diameter.cpp:203:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j = 0 ; j < G[i].size() ; j++) {
                   ~~^~~~~~~~~~~~~
diameter.cpp:190:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%lld", &n, &q, &w);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
diameter.cpp:194:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%lld", &a, &b, &c);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
diameter.cpp:230:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld", &d, &e);
   ~~~~~^~~~~~~~~~~~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 14976 KB Output is correct
2 Correct 9 ms 14976 KB Output is correct
3 Correct 11 ms 15104 KB Output is correct
4 Correct 10 ms 14976 KB Output is correct
5 Correct 10 ms 14976 KB Output is correct
6 Correct 10 ms 14976 KB Output is correct
7 Correct 10 ms 15104 KB Output is correct
8 Correct 10 ms 14976 KB Output is correct
9 Correct 10 ms 15104 KB Output is correct
10 Correct 10 ms 14976 KB Output is correct
11 Correct 10 ms 14976 KB Output is correct
12 Correct 10 ms 14976 KB Output is correct
13 Correct 10 ms 15104 KB Output is correct
14 Correct 10 ms 15104 KB Output is correct
15 Correct 10 ms 14976 KB Output is correct
16 Correct 10 ms 15104 KB Output is correct
17 Correct 10 ms 15104 KB Output is correct
18 Correct 10 ms 15104 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 14976 KB Output is correct
2 Correct 9 ms 14976 KB Output is correct
3 Correct 11 ms 15104 KB Output is correct
4 Correct 10 ms 14976 KB Output is correct
5 Correct 10 ms 14976 KB Output is correct
6 Correct 10 ms 14976 KB Output is correct
7 Correct 10 ms 15104 KB Output is correct
8 Correct 10 ms 14976 KB Output is correct
9 Correct 10 ms 15104 KB Output is correct
10 Correct 10 ms 14976 KB Output is correct
11 Correct 10 ms 14976 KB Output is correct
12 Correct 10 ms 14976 KB Output is correct
13 Correct 10 ms 15104 KB Output is correct
14 Correct 10 ms 15104 KB Output is correct
15 Correct 10 ms 14976 KB Output is correct
16 Correct 10 ms 15104 KB Output is correct
17 Correct 10 ms 15104 KB Output is correct
18 Correct 10 ms 15104 KB Output is correct
19 Correct 39 ms 15352 KB Output is correct
20 Correct 37 ms 15232 KB Output is correct
21 Correct 29 ms 15232 KB Output is correct
22 Correct 19 ms 15232 KB Output is correct
23 Correct 49 ms 15696 KB Output is correct
24 Correct 43 ms 15616 KB Output is correct
25 Correct 31 ms 15744 KB Output is correct
26 Correct 22 ms 16128 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 14976 KB Output is correct
2 Correct 10 ms 14976 KB Output is correct
3 Correct 15 ms 15104 KB Output is correct
4 Correct 62 ms 15232 KB Output is correct
5 Correct 279 ms 15864 KB Output is correct
6 Correct 10 ms 14976 KB Output is correct
7 Correct 9 ms 15104 KB Output is correct
8 Correct 10 ms 15104 KB Output is correct
9 Correct 16 ms 15104 KB Output is correct
10 Correct 69 ms 15352 KB Output is correct
11 Correct 334 ms 15928 KB Output is correct
12 Correct 12 ms 15488 KB Output is correct
13 Correct 12 ms 15488 KB Output is correct
14 Correct 19 ms 15616 KB Output is correct
15 Correct 87 ms 15864 KB Output is correct
16 Correct 332 ms 16376 KB Output is correct
17 Correct 56 ms 24040 KB Output is correct
18 Correct 56 ms 23984 KB Output is correct
19 Correct 69 ms 24168 KB Output is correct
20 Correct 157 ms 24040 KB Output is correct
21 Correct 451 ms 24688 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 15104 KB Output is correct
2 Correct 79 ms 15232 KB Output is correct
3 Correct 389 ms 15788 KB Output is correct
4 Correct 729 ms 16088 KB Output is correct
5 Correct 25 ms 16128 KB Output is correct
6 Correct 127 ms 16376 KB Output is correct
7 Correct 507 ms 16632 KB Output is correct
8 Correct 1059 ms 17808 KB Output is correct
9 Correct 55 ms 20472 KB Output is correct
10 Correct 157 ms 20668 KB Output is correct
11 Correct 694 ms 21624 KB Output is correct
12 Correct 1283 ms 22264 KB Output is correct
13 Correct 79 ms 25976 KB Output is correct
14 Correct 202 ms 26104 KB Output is correct
15 Correct 719 ms 26744 KB Output is correct
16 Correct 1508 ms 27872 KB Output is correct
17 Correct 2079 ms 27512 KB Output is correct

Subtask #5
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 1106 ms 26172 KB Output is correct
2 Correct 1219 ms 26232 KB Output is correct
3 Correct 1188 ms 26104 KB Output is correct
4 Correct 1275 ms 26112 KB Output is correct
5 Correct 1184 ms 25956 KB Output is correct
6 Correct 1062 ms 25708 KB Output is correct
7 Correct 679 ms 29280 KB Output is correct
8 Correct 721 ms 29084 KB Output is correct
9 Correct 553 ms 29176 KB Output is correct
10 Correct 637 ms 29176 KB Output is correct
11 Correct 642 ms 28920 KB Output is correct
12 Correct 430 ms 27884 KB Output is correct
13 Correct 336 ms 34168 KB Output is correct
14 Correct 347 ms 33784 KB Output is correct
15 Correct 350 ms 33912 KB Output is correct
16 Correct 362 ms 33784 KB Output is correct
17 Correct 403 ms 33140 KB Output is correct
18 Correct 350 ms 29548 KB Output is correct
19 Correct 345 ms 34024 KB Output is correct
20 Correct 356 ms 33784 KB Output is correct
21 Correct 341 ms 33976 KB Output is correct
22 Correct 353 ms 33784 KB Output is correct
23 Correct 357 ms 33140 KB Output is correct
24 Correct 317 ms 29596 KB Output is correct

Subtask #6
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 14976 KB Output is correct
2 Correct 9 ms 14976 KB Output is correct
3 Correct 11 ms 15104 KB Output is correct
4 Correct 10 ms 14976 KB Output is correct
5 Correct 10 ms 14976 KB Output is correct
6 Correct 10 ms 14976 KB Output is correct
7 Correct 10 ms 15104 KB Output is correct
8 Correct 10 ms 14976 KB Output is correct
9 Correct 10 ms 15104 KB Output is correct
10 Correct 10 ms 14976 KB Output is correct
11 Correct 10 ms 14976 KB Output is correct
12 Correct 10 ms 14976 KB Output is correct
13 Correct 10 ms 15104 KB Output is correct
14 Correct 10 ms 15104 KB Output is correct
15 Correct 10 ms 14976 KB Output is correct
16 Correct 10 ms 15104 KB Output is correct
17 Correct 10 ms 15104 KB Output is correct
18 Correct 10 ms 15104 KB Output is correct
19 Correct 39 ms 15352 KB Output is correct
20 Correct 37 ms 15232 KB Output is correct
21 Correct 29 ms 15232 KB Output is correct
22 Correct 19 ms 15232 KB Output is correct
23 Correct 49 ms 15696 KB Output is correct
24 Correct 43 ms 15616 KB Output is correct
25 Correct 31 ms 15744 KB Output is correct
26 Correct 22 ms 16128 KB Output is correct
27 Correct 10 ms 14976 KB Output is correct
28 Correct 10 ms 14976 KB Output is correct
29 Correct 15 ms 15104 KB Output is correct
30 Correct 62 ms 15232 KB Output is correct
31 Correct 279 ms 15864 KB Output is correct
32 Correct 10 ms 14976 KB Output is correct
33 Correct 9 ms 15104 KB Output is correct
34 Correct 10 ms 15104 KB Output is correct
35 Correct 16 ms 15104 KB Output is correct
36 Correct 69 ms 15352 KB Output is correct
37 Correct 334 ms 15928 KB Output is correct
38 Correct 12 ms 15488 KB Output is correct
39 Correct 12 ms 15488 KB Output is correct
40 Correct 19 ms 15616 KB Output is correct
41 Correct 87 ms 15864 KB Output is correct
42 Correct 332 ms 16376 KB Output is correct
43 Correct 56 ms 24040 KB Output is correct
44 Correct 56 ms 23984 KB Output is correct
45 Correct 69 ms 24168 KB Output is correct
46 Correct 157 ms 24040 KB Output is correct
47 Correct 451 ms 24688 KB Output is correct
48 Correct 17 ms 15104 KB Output is correct
49 Correct 79 ms 15232 KB Output is correct
50 Correct 389 ms 15788 KB Output is correct
51 Correct 729 ms 16088 KB Output is correct
52 Correct 25 ms 16128 KB Output is correct
53 Correct 127 ms 16376 KB Output is correct
54 Correct 507 ms 16632 KB Output is correct
55 Correct 1059 ms 17808 KB Output is correct
56 Correct 55 ms 20472 KB Output is correct
57 Correct 157 ms 20668 KB Output is correct
58 Correct 694 ms 21624 KB Output is correct
59 Correct 1283 ms 22264 KB Output is correct
60 Correct 79 ms 25976 KB Output is correct
61 Correct 202 ms 26104 KB Output is correct
62 Correct 719 ms 26744 KB Output is correct
63 Correct 1508 ms 27872 KB Output is correct
64 Correct 2079 ms 27512 KB Output is correct
65 Correct 1106 ms 26172 KB Output is correct
66 Correct 1219 ms 26232 KB Output is correct
67 Correct 1188 ms 26104 KB Output is correct
68 Correct 1275 ms 26112 KB Output is correct
69 Correct 1184 ms 25956 KB Output is correct
70 Correct 1062 ms 25708 KB Output is correct
71 Correct 679 ms 29280 KB Output is correct
72 Correct 721 ms 29084 KB Output is correct
73 Correct 553 ms 29176 KB Output is correct
74 Correct 637 ms 29176 KB Output is correct
75 Correct 642 ms 28920 KB Output is correct
76 Correct 430 ms 27884 KB Output is correct
77 Correct 336 ms 34168 KB Output is correct
78 Correct 347 ms 33784 KB Output is correct
79 Correct 350 ms 33912 KB Output is correct
80 Correct 362 ms 33784 KB Output is correct
81 Correct 403 ms 33140 KB Output is correct
82 Correct 350 ms 29548 KB Output is correct
83 Correct 345 ms 34024 KB Output is correct
84 Correct 356 ms 33784 KB Output is correct
85 Correct 341 ms 33976 KB Output is correct
86 Correct 353 ms 33784 KB Output is correct
87 Correct 357 ms 33140 KB Output is correct
88 Correct 317 ms 29596 KB Output is correct
89 Correct 1032 ms 29048 KB Output is correct
90 Correct 886 ms 29304 KB Output is correct
91 Correct 640 ms 30840 KB Output is correct
92 Correct 639 ms 30968 KB Output is correct
93 Correct 452 ms 33628 KB Output is correct
94 Correct 551 ms 32632 KB Output is correct
95 Correct 422 ms 34428 KB Output is correct
96 Correct 443 ms 33272 KB Output is correct
97 Correct 422 ms 34296 KB Output is correct
98 Correct 364 ms 36600 KB Output is correct
99 Correct 375 ms 34168 KB Output is correct
100 Correct 371 ms 34044 KB Output is correct