Submission #1239795

#	Time	Username	Problem	Language	Result	Execution time	Memory
1239795		hainam2k9	Pictionary (COCI18_pictionary)	C++20	140 / 140	64 ms	23880 KiB

pictionary

#include <bits/stdc++.h>
#define tt cin.tie(0), cout.tie(0), ios_base::sync_with_stdio(0)
#define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
#define ll long long
#define ull unsigned long long
#define i128 __int128
#define db long double
#define sz(a) ((int)(a).size())
#define pb emplace_back
#define pf emplace_front
#define pob pop_back
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
#define fi first
#define se second
#define ins emplace
#define mp make_pair
using namespace std;
const int MOD = 1e9+7, MAXN = 1e5+5;
const string NAME = "";
int n,m,q,depth[MAXN];
pair<int,int> par[MAXN][20];
vector<pair<int,int>> adj[MAXN];
struct DSU{
    int p[MAXN],sz[MAXN];
    void init(int n){
        iota(p+1,p+n+1,1);
        fill(sz+1,sz+n+1,1);
    }
    int Find(int u){
        if(u==p[u]) return u;
        return p[u]=Find(p[u]);
    }
    void Union(int x, int y){
        x=Find(x), y=Find(y);
        if(x==y) return;
        if(sz[x]<sz[y]) swap(x,y);
        p[y]=x, sz[x]+=sz[y];
    }
}dsu;
void dfs(int u){
    for(pair<int,int>& e : adj[u])
        if(e.fi!=par[u][0].fi){
            depth[e.fi]=depth[u]+1, par[e.fi][0]={u,e.se};
            for(int i = 1; i<=__lg(n); ++i){
                par[e.fi][i].fi=par[par[e.fi][i-1].fi][i-1].fi;
                par[e.fi][i].se=max(par[e.fi][i-1].se,par[par[e.fi][i-1].fi][i-1].se);
            }
            dfs(e.fi);
        }
}
inline int lift(int x, int k){
    for(int i = 0; i<=__lg(n); ++i)
        if((k>>i)&1) x=par[x][i].fi;
    return x;
}
int LCA(int x, int y){
    if(depth[x]!=depth[y]){
        if(depth[x]<depth[y]) swap(x,y);
        x=lift(x,depth[x]-depth[y]);
    }
    if(x==y) return x;
    for(int i = __lg(n); i>=0; --i)
        if(par[x][i].fi!=par[y][i].fi) x=par[x][i].fi, y=par[y][i].fi;
    return par[x][0].fi;
}
int main()
{
    tt;
    if(fopen((NAME + ".INP").c_str(), "r")) fo;
    cin >> n >> m >> q;
    dsu.init(n);
    for(int i = m; i>0; --i)
        for(int j = i<<1; j<=n; j+=i)
            if(dsu.Find(i)!=dsu.Find(j)){
                dsu.Union(i,j);
                adj[i].pb(j,m-i+1), adj[j].pb(i,m-i+1);
            }
    dfs(1);
    while(q--){
        int x,y,lca,rs=0;
        cin >> x >> y;
        lca=LCA(x,y);
        for(int i = __lg(n); i>=0; --i){
            if(par[x][i].fi!=0&&depth[par[x][i].fi]>=depth[lca]) rs=max(rs,par[x][i].se), x=par[x][i].fi;
            if(par[y][i].fi!=0&&depth[par[y][i].fi]>=depth[lca]) rs=max(rs,par[y][i].se), y=par[y][i].fi;
        }
        cout << rs << "\n";
    }
}

Compilation message (stderr)

pictionary.cpp: In function 'int main()':
pictionary.cpp:3:19: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pictionary.cpp:71:45: note: in expansion of macro 'fo'
   71 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~
pictionary.cpp:3:63: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |                                                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pictionary.cpp:71:45: note: in expansion of macro 'fo'
   71 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 14 / 14
• Subtask 6: 14 / 14
• Subtask 7: 14 / 14
• Subtask 8: 14 / 14
• Subtask 9: 14 / 14
• Subtask 10: 14 / 14