//how ? boruvska + lca
#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 = 1e5 + 5;
const int logn = log2(maxn) + 1;
int n , m , q;
vector<ii> adj[maxn];
int vis[maxn];
int lab[maxn];
int FindLab(int u){
return lab[u] < 0 ? u : lab[u] = FindLab(lab[u]);
}
void Merge(int u , int v , int c){
u = FindLab(u) , v = FindLab(v);
if(u == v)return;
if(lab[u] > lab[v])swap(u , v);
lab[u] += lab[v];lab[v] = u;
adj[u].pb(mp(v,c));
adj[v].pb(mp(u,c));
}
int M[maxn][logn] , P[maxn][logn];
int dep[maxn];
void dfs(int u , int par){
for(auto & c : adj[u]){
if(c.first == par)continue;
M[c.first][0] = c.second;
P[c.first][0] = u;
dep[c.first] = dep[u] + 1;
for(int i = 1 ; i < logn ; ++i){
P[c.first][i] = P[P[c.first][i - 1]][i - 1];
M[c.first][i] = max(M[c.first][i - 1] , M[P[c.first][i - 1]][i - 1]);
}
dfs(c.first , u);
}
}
int getm(int u , int v){
int res = 0;
if(dep[u] < dep[v])swap(u , v);
for(int i = 0 ; i < logn ; ++i){
if((dep[u] - dep[v]) & (1 << i)){
res = max(res , M[u][i]);
u = P[u][i];
}
}
if(u == v)return res;
for(int i = logn - 1 ; i >= 0 ; --i){
if(P[u][i] != P[v][i]){
res = max(res , M[u][i]);
res = max(res , M[v][i]);
u = P[u][i];
v = P[v][i];
}
}
res = max(res , M[u][0]);
res = max(res , M[v][0]);
return res;
}
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);
}
memset(lab,-1,sizeof lab);
cin >> n >> m >> q;
for(int i = m ; i >= 1 ; --i){
int a = -1 , b = -1;
for(int j = i * 2 ; j <= n ; j += i){
Merge(i,j,m+1-i);
}
}
dfs(1,0);
while(q--){
int u , v;cin >> u >> v;
cout << getm(u , v) << '\n';
}
}
Compilation message
pictionary.cpp: In function 'int main()':
pictionary.cpp:89:13: warning: unused variable 'a' [-Wunused-variable]
int a = -1 , b = -1;
^
pictionary.cpp:89:22: warning: unused variable 'b' [-Wunused-variable]
int a = -1 , b = -1;
^
pictionary.cpp:83:10: 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);
~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
pictionary.cpp:84:10: 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);
~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
3328 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
3456 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
4096 KB |
Output is correct |
2 |
Correct |
24 ms |
4096 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
40 ms |
4600 KB |
Output is correct |
2 |
Correct |
33 ms |
4472 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
34 ms |
7800 KB |
Output is correct |
2 |
Correct |
31 ms |
7800 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
47 ms |
9720 KB |
Output is correct |
2 |
Correct |
57 ms |
10312 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
59 ms |
12408 KB |
Output is correct |
2 |
Correct |
61 ms |
12664 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
76 ms |
15340 KB |
Output is correct |
2 |
Correct |
99 ms |
17144 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
105 ms |
18552 KB |
Output is correct |
2 |
Correct |
103 ms |
20600 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
123 ms |
22652 KB |
Output is correct |
2 |
Correct |
120 ms |
22848 KB |
Output is correct |