Submission #245650

#	Time	Username	Problem	Language	Result	Execution time	Memory
245650		Mercenary	Birthday gift (IZhO18_treearray)	C++14	100 / 100	1450 ms	82644 KiB

treearray

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>

#define pb push_back
#define mp make_pair
#define taskname "A"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef tree <int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

const int maxn = 2e5 + 5;
const int mod = 1e9 + 7;
const int logn = log2(maxn) + 1;

int n , m , q;
vector<int> adj[maxn];
int a[maxn];
int P[maxn][logn] , dep[maxn];
void dfs(int u , int par){
    for(auto c : adj[u]){
        if(c == par)continue;
        dep[c] = dep[u] + 1;
        P[c][0] = u;
        for(int i = 1 ; i < logn ; ++i)P[c][i] = P[P[c][i - 1]][i - 1];
        dfs(c , u);
    }
}

int lca(int u , int v){
    if(dep[u] < dep[v])swap(u ,v);
    for(int i = 0 ; i < logn ; ++i)if((dep[u] - dep[v]) & (1 << i))u = P[u][i];
    if(u == v)return u;
    for(int i = logn - 1 ; i >= 0 ; --i){
        if(P[u][i] != P[v][i]){
            u = P[u][i];
            v = P[v][i];
        }
    }
    return P[u][0];
}
set<int> s[maxn] , s1[maxn];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n >> m >> q;
    for(int i = 1 ; i < n ; ++i){
        int u , v;cin >> u >> v;
        adj[u].pb(v);adj[v].pb(u);
    }
    for(int i = 1 ; i <= m ; ++i)cin >> a[i];
    dfs(1 , 0);
    for(int i = 1 ; i < m ; ++i){
        s1[lca(a[i] , a[i + 1])].insert(i);
    }
    for(int i = 1 ; i <= m ; ++i){
        s[a[i]].insert(i);
    }
    while(q--){
        int type;cin >> type;
        if(type == 1){
            int i , v;cin >> i >> v;
            if(a[i] == v)continue;
            s[a[i]].erase(i);
            if(i > 1)s1[lca(a[i],a[i - 1])].erase(i - 1);
            if(i + 1 <= m)s1[lca(a[i] , a[i + 1])].erase(i);
            a[i] = v;
            s[a[i]].insert(i);
            if(i > 1)s1[lca(a[i],a[i - 1])].insert(i - 1);
            if(i + 1 <= m)s1[lca(a[i] , a[i + 1])].insert(i);
        }else{
            int l , r  , v;cin >> l >> r >> v;
            auto it = s[v].lower_bound(l);
            if(it == s[v].end() || *it > r){
                auto it1 = s1[v].lower_bound(l);
                if(it1 == s1[v].end() || *it1 + 1 > r){
                    cout << -1 << " " << -1 << '\n';
                }else{
                    cout << *it1 << " " << *it1 + 1 << '\n';
                }
            }else{
                cout << *it << " " << *it << '\n';
            }
        }
    }
}

Compilation message (stderr)

treearray.cpp: In function 'int main()':
treearray.cpp:54:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
treearray.cpp:55:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44