Submission #492326

#	Time	Username	Problem	Language	Result	Execution time	Memory
492326		Vladth11	Pictionary (COCI18_pictionary)	C++14	126 / 140	285 ms	65536 KiB

pictionary

#include <bits/stdc++.h>
#define debug(x) cerr << #x << " " << x << "\n"
#define debugs(x) cerr << #x << " " << x << " "
 
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
 
const int NMAX = 100001;
const int nr_of_bits = 14;
 
int n, m, q;
vector <int> divs[NMAX];
 
struct edge{
    int from, to, cost;
};
 
vector <edge> edges;
 
void addEdge(int a, int b, int c){
    edges.push_back({a, b, c});
    edges.push_back({a, b, c});
}
 
bool cmp(edge a, edge b){
    return a.cost < b.cost;
}
 
int p[2 * NMAX];
int cnt[2 * NMAX];
 
int root(int x){
    if(p[x] == x)
        return x;
    return p[x] = root(p[x]);
}
 
vector <pii> v[2 * NMAX];
 
void unite(int a, int b, int cost){
    if(root(a) == root(b))
        return;
    v[a].push_back({b, cost});
    v[b].push_back({a, cost});
    a = root(a);
    b = root(b);
    if(cnt[a] < cnt[b])
        swap(a, b);
    p[b] = a;
    cnt[a] += cnt[b];
}
 
int dp[NMAX * 2][nr_of_bits + 1];
int cost[NMAX * 2][nr_of_bits + 1];
pii timp[2 * NMAX];
int stamp;
 
bool isParent(int a, int b){
    return (timp[a].first <= timp[b].first && timp[b].second <= timp[a].second);
}
 
void DFS(int node, int p){
    dp[node][0] = p;
    timp[node].first = ++stamp;
    for(auto x : v[node]){
        if(x.first == p)
            continue;
        cost[x.first][0] = x.second;
        DFS(x.first, node);
    }
    timp[node].second = ++stamp;
}
 
int LCA(int a, int b){
    int r = a, pas = nr_of_bits;
    while(pas >= 0){
        int nxt = dp[r][pas];
        if(nxt != 0 && !isParent(nxt, b))
            r = nxt;
        pas--;
    }
    if(!isParent(r, b))
        r = dp[r][0];
    return r;
}
 
int drum(int r, int lca){
    int pas = nr_of_bits;
    int maxim = 0;
    while(pas >= 0){
        int nxt = dp[r][pas];
        if(nxt != 0 && !isParent(nxt, lca)){
            maxim = max(maxim, cost[r][pas]);
            r = nxt;
        }
        pas--;
    }
    if(r != lca)
        maxim = max(maxim, cost[r][0]);
    return maxim;
}
 
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m >> q;
    for(int i = 1; i < NMAX; i++){
        for(int j = i; j < NMAX; j+=i){
            divs[i].push_back(j);
        }
    }
    for(int i = 1; i <= n + m; i++){
        p[i] = i;
        cnt[i] = 1;
    }
    for(int i = m; i >= 1; i--){
        for(auto x : divs[i]){
            if(x > n)
                break;
            addEdge(x, n + i, (m - i + 1));
        }
    }
    sort(edges.begin(), edges.end(), cmp);
    for(auto x : edges){
        unite(x.from, x.to, x.cost);
    }
    DFS(1, 0);
    for(int j = 1; j <= nr_of_bits; j++){
        for(int i = 1; i <= n + m; i++){
            dp[i][j] = dp[dp[i][j - 1]][j - 1];
            cost[i][j] = max(cost[i][j - 1], cost[dp[i][j - 1]][j - 1]);
        }
    }
    while(q--){
        int x, y;
        cin >> x >> y;
        int lca = LCA(x, y);
        cout << max(drum(x, lca), drum(y, lca)) << "\n";
    }
    return 0;
}

• 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: 0 / 14