Submission #1166891

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166891		SmuggingSpun	Birthday gift (IZhO18_treearray)	C++20	30 / 100	4091 ms	1328 KiB

treearray

#include<bits/stdc++.h>
#define taskname "C"
using namespace std;
template<class T>void minimize(T& a, T b){
    if(a > b){
        a = b;
    }
}
template<class T>void maximize(T& a, T b){
    if(a < b){
        a = b;
    }
}
int n, m, q;
namespace sub1{
    void solve(){
        vector<vector<int>>g(n + 1);
        for(int i = 1; i < n; i++){
            int u, v;
            cin >> u >> v;
            g[u].emplace_back(v);
            g[v].emplace_back(u);
        }
        vector<int>parent(n + 1), h(n + 1);
        function<void(int)>dfs;
        dfs = [&] (int s){
            for(int& d : g[s]){
                if(d != parent[s]){
                    h[d] = h[parent[d] = s] + 1;
                    dfs(d);
                }
            }
        };
        dfs(parent[1] = h[1] = 1);
        auto lca = [&] (int u, int v){
            while(u != v){
                if(h[u] < h[v]){
                    swap(u, v);
                }
                u = parent[u];
            }
            return u;
        };
        vector<int>a(m + 1);
        for(int i = 1; i <= m; i++){
            cin >> a[i];
        }
        for(int _ = 0; _ < q; _++){
            int _t;
            cin >> _t;
            if(_t == 1){
                int p;
                cin >> p >> a[p];
            }
            else{
                int l, r, v;
                cin >> l >> r >> v;
                int L = -1, R = -1;
                for(int i = l; i <= r && L == -1; i++){
                    int u = a[i];
                    for(int j = i; j <= r; j++){
                        if((u = lca(u, a[j])) == v){
                            L = i;
                            R = j;
                            break;
                        }
                    }
                }
                cout << L << " " << R << "\n";
            }
        }
    }
}
namespace sub23{
    void solve(){
        vector<vector<int>>g(n + 1);
        for(int i = 1; i < n; i++){
            int u, v;
            cin >> u >> v;
            g[u].emplace_back(v);
            g[v].emplace_back(u);
        }
        vector<int>fir(n + 1), las(n + 1), h(n + 1), euler;
        function<void(int, int)>dfs;
        dfs = [&] (int s, int p){
            fir[s] = las[s] = euler.size();
            euler.emplace_back(s);
            for(int& d : g[s]){
                if(d != p){
                    dfs(d, s);
                    las[s] = euler.size();
                    euler.emplace_back(s);
                }
            }
        };
        dfs(1, h[1] = 0);
        vector<vector<pair<int, int>>>spt(euler.size(), vector<pair<int, int>>(12));
        vector<int>log_v(euler.size() + 1);
        log_v[0] = -1;
        for(int i = 0; i < euler.size(); i++){
            spt[i][0] = make_pair(h[euler[i]], euler[i]);
            log_v[i + 1] = log_v[(i + 1) >> 1] + 1;
        }
        for(int j = 1; j < 12; j++){
            for(int i = 0; i + (1 << j) <= euler.size(); i++){
                spt[i][j] = min(spt[i][j - 1], spt[i + (1 << (j - 1))][j - 1]);
            }
        }
        auto lca = [&] (int L, int R){
            int k = log_v[R - L + 1];
            return min(spt[L][k], spt[R - (1 << k) + 1][k]).second;
        };
        vector<int>a(m + 1);
        for(int i = 1; i <= m; i++){
            cin >> a[i];
        }
        for(int _ = 0; _ < q; _++){
            int _t;
            cin >> _t;
            if(_t == 1){
                int p;
                cin >> p >> a[p];
            }
            else{
                int l, r, v, l_ans = -1, r_ans = -1;
                cin >> l >> r >> v;
                for(int i = l; i <= r && l_ans == -1; i++){
                    int L = euler.size(), R = 0;
                    for(int j = i; j <= r; j++){
                        minimize(L, fir[a[j]]);
                        maximize(R, las[a[j]]);
                        if(lca(L, R) == v){
                            l_ans = i;
                            r_ans = j;
                            break;
                        }
                    }
                }
                cout << l_ans << " " << r_ans << "\n";
            }
        }
    }
}
namespace sub4{
    void solve(){

    }
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
    cin >> n >> m >> q;
    if(max({n, m, q}) <= 100){
        sub1::solve();
    }
    else if(max({n, m, q}) <= 2000){
        sub23::solve();
    }
    else{
        sub4::solve();
    }
}

Compilation message (stderr)

treearray.cpp: In function 'int main()':
treearray.cpp:152:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  152 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 0 / 26
• Subtask 4: 0 / 44