oj.uz

Submission #938501

# Submission time Handle Problem Language Result Execution time Memory
938501 2024-03-05T08:20:09 Z Baizho Valley (BOI19_valley) C++14
100 / 100
 171 ms 42280 KB 
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
  
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
 
// #pragma GCC optimize("Ofast,unroll-loops,fast-math")
// #pragma GCC target("popcnt")


typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> pll;
 
#define sz size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define pb push_back

const int mod = ll(1e9)+7; //(b + (a%b)) % b (to mod -1%(10^9+7) correctly in c++ its -1 but its suppose to be 10^9+6
const ll MOD = 998244353;  // (a%mod)*(binpow(b,mod-2,mod) = (a/b)%mod
const int N = ll(1e5)+100;
const long long inf = 2e18;
const long double eps = 1e-15L;
 
ll lcm(ll a, ll b) { return (a / __gcd(a,b))*b; }

ll binpow(ll a, ll b, ll m) { ll res=1; a %= m; while(b>0){ if(b&1)res=(res * a) % m; a=(a * a) % m; b/=2; } return res%m;}


void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }

int n, s, q, e, depth[N], up[20][N], qu[N], qv[N], qw[N];
ll lift[20][N];
bool shop[N];
ll mn[N], dis[N];
vector<pair<int, int> > g[N];

void dfs(int v, int p = 0) {
	if(!shop[v]) mn[v] = inf;
	up[0][v] = p;
	for(int j = 1; j <= 17; j ++) up[j][v] = up[j - 1][up[j - 1][v]];
	for(auto to : g[v]) {
		if(p == to.ff) continue;
		depth[to.ff] = depth[v] + 1;
		dis[to.ff] = dis[v] + to.ss;
		
		dfs(to.ff, v);
		if(mn[to.ff] != inf) mn[v] = min(mn[v], mn[to.ff] + to.ss);
	}
}

void dfs1(int v, int p = 0) {
	lift[0][v] = mn[v] - dis[v];
	for(int j = 1; j <= 17; j ++) lift[j][v] = min(lift[j - 1][v], lift[j - 1][up[j - 1][v]]);
	for(auto to : g[v]) {
		if(p == to.ff) continue;
		dfs1(to.ff, v);
	}
}

int lca(int u, int v) {
	if(depth[u] < depth[v]) swap(u, v);
	// u is down further
	int dif = depth[u] - depth[v];
	for(int i = 17; i >= 0; i --) {
		if(dif & (1<<i)) u = up[i][u];
	}
//	cout<<u<<" "<<v<<"\n";
	if(u == v) return u;
	for(int i = 17; i >= 0; i --) {
		if(up[i][u] != up[i][v]) {
			u = up[i][u];
			v = up[i][v];
		}
	}
	return up[0][v];
}

ll getmn(int v, int cnt) {
	ll res = inf;
	for(int j = 17; j >= 0; j --) {
		if(cnt & (1 << j)) {
			res = min(res, lift[j][v]);
			v = up[j][v];
		}
	}
	return res;
}

void Baizho() {	
	cin>>n>>s>>q>>e;
	for(int i = 1; i <= n - 1; i ++) {
		int u, v, w; cin>>u>>v>>w;
		qu[i] = u;
		qv[i] = v;
		g[u].pb({v, w});
		g[v].pb({u, w});
	}
	for(int i = 1; i <= s; i ++) {
		int v; cin>>v;
		shop[v] = 1;
	}
	dfs(e);
	dfs1(e);
	for(int i = 1; i <= n - 1; i ++) {
		if(depth[qu[i]] > depth[qv[i]]) swap(qu[i], qv[i]);
	}
	while(q --) {
		int id, r; cin>>id>>r;
		// qu[id] has less depth than qv[id]
//		cout<<lca(r, qv[id])<<" thelca \n";
		if(lca(r, qv[id]) != qv[id]) cout<<"escaped\n";
		else {
			if(mn[qv[id]] == inf) cout<<"oo\n";
			else {
				cout<<getmn(r, depth[r] - depth[qv[id]] + 1) + dis[r]<<"\n";
			}
		}
	}
}
 
signed main() {		
 
    ios_base::sync_with_stdio(false);   
    cin.tie(0);cout.tie(0); 
//   	precalc();
   	
    int ttt = 1;
//    cin>>ttt;

    for(int i=1; i<=ttt; i++) {Baizho(); }
}

Compilation message

valley.cpp: In function 'void Freopen(std::string)':
valley.cpp:35:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 | void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                           ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:35:76: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 | void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                                                                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 29276 KB Output is correct
2 Correct 6 ms 29276 KB Output is correct
3 Correct 6 ms 29272 KB Output is correct
4 Correct 6 ms 29276 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 29276 KB Output is correct
2 Correct 6 ms 29276 KB Output is correct
3 Correct 6 ms 29272 KB Output is correct
4 Correct 6 ms 29276 KB Output is correct
5 Correct 4 ms 29276 KB Output is correct
6 Correct 7 ms 29276 KB Output is correct
7 Correct 4 ms 29276 KB Output is correct
8 Correct 4 ms 29276 KB Output is correct
9 Correct 4 ms 29408 KB Output is correct
10 Correct 5 ms 29276 KB Output is correct
11 Correct 4 ms 29276 KB Output is correct
12 Correct 4 ms 29276 KB Output is correct
13 Correct 4 ms 29276 KB Output is correct
14 Correct 4 ms 29276 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 119 ms 37736 KB Output is correct
2 Correct 131 ms 37460 KB Output is correct
3 Correct 139 ms 37456 KB Output is correct
4 Correct 154 ms 39252 KB Output is correct
5 Correct 146 ms 39408 KB Output is correct
6 Correct 169 ms 41108 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 29276 KB Output is correct
2 Correct 6 ms 29276 KB Output is correct
3 Correct 6 ms 29272 KB Output is correct
4 Correct 6 ms 29276 KB Output is correct
5 Correct 4 ms 29276 KB Output is correct
6 Correct 7 ms 29276 KB Output is correct
7 Correct 4 ms 29276 KB Output is correct
8 Correct 4 ms 29276 KB Output is correct
9 Correct 4 ms 29408 KB Output is correct
10 Correct 5 ms 29276 KB Output is correct
11 Correct 4 ms 29276 KB Output is correct
12 Correct 4 ms 29276 KB Output is correct
13 Correct 4 ms 29276 KB Output is correct
14 Correct 4 ms 29276 KB Output is correct
15 Correct 119 ms 37736 KB Output is correct
16 Correct 131 ms 37460 KB Output is correct
17 Correct 139 ms 37456 KB Output is correct
18 Correct 154 ms 39252 KB Output is correct
19 Correct 146 ms 39408 KB Output is correct
20 Correct 169 ms 41108 KB Output is correct
21 Correct 102 ms 37208 KB Output is correct
22 Correct 124 ms 37084 KB Output is correct
23 Correct 147 ms 36944 KB Output is correct
24 Correct 129 ms 39044 KB Output is correct
25 Correct 167 ms 42280 KB Output is correct
26 Correct 113 ms 37212 KB Output is correct
27 Correct 118 ms 36948 KB Output is correct
28 Correct 120 ms 36948 KB Output is correct
29 Correct 157 ms 38340 KB Output is correct
30 Correct 153 ms 39764 KB Output is correct
31 Correct 103 ms 37456 KB Output is correct
32 Correct 125 ms 37200 KB Output is correct
33 Correct 126 ms 37148 KB Output is correct
34 Correct 142 ms 38740 KB Output is correct
35 Correct 171 ms 41700 KB Output is correct
36 Correct 143 ms 39008 KB Output is correct