oj.uz

Submission #36010

# Submission time Handle Problem Language Result Execution time Memory
36010 2017-12-04T08:16:24 Z ngkan146 Election Campaign (JOI15_election_campaign) C++
10 / 100
 413 ms 40252 KB 
#include <bits/stdc++.h>
#define ll long long
using namespace std;
struct query{
	int a,b,val;
	query(int a=0,int b=0,int val=0): a(a), b(b), val(val) {}
};
int n,m,lv[100005], beg[100005], fin[100005], p[100005][20], ___time;
vector <int> G[100005];
vector <query> Q[100005];
void dfs(int u){
	for(int k=1;k<20;k++)
		p[u][k] = p[p[u][k-1]][k-1];
	beg[u] = ++___time;
	for(int i=0;i<(int)G[u].size();i++){
		int v = G[u][i];
		if (v == p[u][0]) continue;
		p[v][0] = u;
		lv[v] = lv[u]+1;
		dfs(v);
	}
	fin[u] = ___time;
}
int lca(int x,int y){
	for(int k=19;k>=0;k--)	if (lv[p[x][k]] >= lv[y]) x = p[x][k];
	for(int k=19;k>=0;k--)	if (lv[p[y][k]] >= lv[x]) y = p[y][k];
	if (x == y) return x;
	for(int k=19;k>=0;k--)	if (p[x][k] != p[y][k])	x = p[x][k], y = p[y][k];
	return p[x][0];
}
ll seg[400005], lazy[400005];
void _lazy(int id,int l,int r){
	seg[id] += lazy[id] * (r - l + 1);
	if (l != r){
		lazy[2*id] += lazy[id];
		lazy[2*id+1] += lazy[id];
	}
	lazy[id] = 0;
}
void seg_upd(int id,int l,int r,int u,int v,ll val){
	_lazy(id,l,r);
	if (r < u || v < l) return;
	if (u <= l && r <= v){
		lazy[id] += val;
		_lazy(id,l,r);
		return;
	}
	seg_upd(2*id, l, (l+r)/2, u, v, val);
	seg_upd(2*id+1, (l+r)/2+1, r, u, v, val);
	seg[id] = seg[2*id] + seg[2*id+1];
}
ll seg_get(int id,int l,int r,int pos){
	if (r < pos || pos < l)		return 0;
	if (l == r)	return seg[id];
	return seg_get(2*id, l, (l+r)/2, pos) + seg_get(2*id+1, (l+r)/2+1, r, pos);
}
ll dp[100005];
ll get_decendant(int x,int y){
	int l = 0, r = G[x].size();
	while(l+1 < r){
		int mid = (l+r)/2;
		int z = G[x][mid];
		if (beg[y] < beg[z])	r = mid;
		else l = mid; 
	}
	return G[x][l];
}
void solve(int u){
	ll sum = 0;
	//cout << u << ' ' << p[u][0] << endl;
	for(int i=0;i<(int)G[u].size();i++){
		if (G[u][i] != p[u][0])	
			solve(G[u][i]), 
			sum += dp[G[u][i]];
	}
	
	dp[u] = sum;
	for(int id=0;id<(int)Q[u].size();id++){
		int a = Q[u][id].a;
		int b = Q[u][id].b;
		int val = Q[u][id].val;
		//cout << "Q" << u << ' ' << a << ' ' << b << endl;
		if (a == u)
			dp[u] = max(dp[u], seg_get(1,1,n,beg[b]) + sum - dp[get_decendant(u,b)] + val); 
		else if (b == u)
			dp[u] = max(dp[u], seg_get(1,1,n,beg[a]) + sum - dp[get_decendant(u,a)] + val);
		else
			dp[u] = max(dp[u], sum + seg_get(1,1,n,beg[a]) + seg_get(1,1,n,beg[b]) - dp[get_decendant(u,a)] - dp[get_decendant(u,b)] + val);
	}
	for(int i=0;i<(int)G[u].size();i++){
		int v = G[u][i];
		if (v == p[u][0]) continue;
		seg_upd(1,1,n,beg[v],fin[v], sum - dp[v]);
	}
	seg_upd(1,1,n,beg[u],beg[u], sum);
	//cout << "res " << u << ' ' << dp[u] << endl;
	
}
bool cmp(int x,int y){
	return beg[x] < beg[y];
}
int main(){
	scanf("%d",&n);
	for(int i=1;i<n;i++){
		int x,y;
		scanf("%d %d",&x,&y);
		G[x].push_back(y);
		G[y].push_back(x);
	}
	lv[1] = 1;
	dfs(1);
	scanf("%d",&m);
	for(int i=1;i<=m;i++){
		int a,b,val;
		scanf("%d %d %d",&a,&b,&val);
		Q[lca(a,b)].push_back(query(a,b,val));
	}
	for(int i=1;i<=n;i++)	sort(G[i].begin(), G[i].end(), cmp);
	solve(1);
	cout << dp[1];
}
/*
7
3 4
6 5
2 7
1 5
7 5
4 5
5
4 3 10
5 6 5
2 6 9
7 2 2
1 3 8
*/

Compilation message

election_campaign.cpp: In function 'int main()':
election_campaign.cpp:103:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
                ^
election_campaign.cpp:106:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d",&x,&y);
                       ^
election_campaign.cpp:112:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&m);
                ^
election_campaign.cpp:115:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d",&a,&b,&val);
                               ^

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 22724 KB Output is correct
2 Correct 0 ms 22724 KB Output is correct
3 Correct 3 ms 22724 KB Output is correct
4 Correct 0 ms 22724 KB Output is correct
5 Incorrect 216 ms 26024 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 22724 KB Output is correct
2 Correct 0 ms 22724 KB Output is correct
3 Correct 3 ms 22724 KB Output is correct
4 Correct 333 ms 40244 KB Output is correct
5 Correct 333 ms 40248 KB Output is correct
6 Correct 293 ms 40248 KB Output is correct
7 Correct 343 ms 40248 KB Output is correct
8 Correct 309 ms 40252 KB Output is correct
9 Correct 293 ms 40252 KB Output is correct
10 Correct 343 ms 40248 KB Output is correct

Subtask #3
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 22724 KB Output is correct
2 Correct 0 ms 22724 KB Output is correct
3 Correct 3 ms 22724 KB Output is correct
4 Correct 333 ms 40244 KB Output is correct
5 Correct 333 ms 40248 KB Output is correct
6 Correct 293 ms 40248 KB Output is correct
7 Correct 343 ms 40248 KB Output is correct
8 Correct 309 ms 40252 KB Output is correct
9 Correct 293 ms 40252 KB Output is correct
10 Correct 343 ms 40248 KB Output is correct
11 Correct 19 ms 23252 KB Output is correct
12 Correct 326 ms 40244 KB Output is correct
13 Correct 336 ms 40244 KB Output is correct
14 Correct 289 ms 40248 KB Output is correct
15 Correct 283 ms 40248 KB Output is correct
16 Correct 296 ms 40248 KB Output is correct
17 Correct 336 ms 40252 KB Output is correct
18 Correct 279 ms 40248 KB Output is correct
19 Correct 299 ms 40248 KB Output is correct
20 Correct 276 ms 40244 KB Output is correct

Subtask #4
0 / 30.0

# Verdict Execution time Memory Grader output
1 Incorrect 413 ms 27764 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 22724 KB Output is correct
2 Correct 0 ms 22724 KB Output is correct
3 Correct 3 ms 22724 KB Output is correct
4 Correct 0 ms 22724 KB Output is correct
5 Incorrect 216 ms 26024 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #6
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 22724 KB Output is correct
2 Correct 0 ms 22724 KB Output is correct
3 Correct 3 ms 22724 KB Output is correct
4 Correct 0 ms 22724 KB Output is correct
5 Incorrect 216 ms 26024 KB Output isn't correct
6 Halted 0 ms 0 KB -