#include "highway.h"
#include <iostream>
#include <vector>
#include <cstring>
using namespace std;
const int MAXN=1e5+10;
vector <pair <int,int> > v[MAXN], dist;
vector <int> w;
bool used[MAXN];
long long depth[MAXN], par[MAXN];
int edge;
long long a, b, path;
int n;
void find_tree(int x) {
used[x]=true;
for (auto i:v[x]) {
if (i.second==edge) continue;
if (used[i.first]) continue;
w[i.second]=1;
depth[i.first]=depth[x]+1;
par[i.first]=i.second;
find_tree(i.first);
}
}
int find_one(int start) {
for (int i=0;i<n-1;i++) w[i]=0;
memset(used,false,sizeof(used));
memset(depth,0,sizeof(depth));
find_tree(start);
long long d=path/a;
if (d==0) return start;
if (!dist.empty()) dist.clear();
for (int i=0;i<n;i++) {
if (depth[i]==d) dist.push_back({i,par[i]});
}
int l, r, mid;
l=0; r=dist.size()-1;
while (l<r) {
mid=(l+r)/2;
for (int i=0;i<n-1;i++) w[i]=0;
for (int i=l;i<=mid;i++) w[dist[i].second]=1;
long long cur=ask(w);
if (cur==path) l=mid+1;
else r=mid;
}
return dist[l].first;
}
void find_pair (int N, vector <int> U, vector <int> V, int A, int B) {
n=N; a=A; b=B;
w.resize(n-1);
for (int i=0;i<U.size();i++) {
v[U[i]].push_back({V[i],i});
v[V[i]].push_back({U[i],i});
}
for (int i=0;i<n-1;i++) w[i]=0;
path=ask(w);
edge=-1;
int ans1, ans2;
int l, r, mid;
l=0; r=n-1;
while (l<r) {
mid=(l+r)/2;
for (int i=0;i<n-1;i++) w[i]=0;
for (int i=l;i<=mid;i++) w[i]=1;
long long cur=ask(w);
if (cur==path) l=mid+1;
else r=mid;
}
edge=l;
ans1=find_one(U[edge]);
ans2=find_one(V[edge]);
answer(ans1,ans2);
}
Compilation message
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:51:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
51 | for (int i=0;i<U.size();i++) {
| ~^~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
4276 KB |
Output is incorrect: {s, t} is wrong. |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
7 ms |
8432 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
9 ms |
5392 KB |
Output is incorrect: {s, t} is wrong. |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
4336 KB |
Output is incorrect: {s, t} is wrong. |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
8 ms |
4696 KB |
Incorrect |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
18 ms |
4868 KB |
Incorrect |
2 |
Halted |
0 ms |
0 KB |
- |