#include "highway.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
// ll ask(vector<int> w)
// void answer(int a, int b)
vector<vector<pair<int,int>>> adjlist; // node, ind
int n,a,b,m;
vector<int> parentedge;
vector<int> parentnode;
vector<int> preorder;
void dfs(int node, int par){
preorder.push_back(node);
for (auto p : adjlist[node]){
int i = p.first;
int ni = p.second;
if (i==par){continue;}
parentnode[i]=node;
parentedge[i]=ni;
dfs(i,node);
}
}
void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B) {
n=N;a=A;b=B;m=U.size();
adjlist.resize(n);
parentnode.resize(n,-1);
parentedge.resize(n,-1);
for (int i = 0; i<U.size(); i++){
adjlist[U[i]].push_back({V[i],i});
adjlist[V[i]].push_back({U[i],i});
}
dfs(0,-1);
// what's the total length of the path?
vector<int> query(m);
ll len = ask(query)/a;
// binary search until path is len*b
int l = 0, r = n-1;
while (l<=r){
int mid = (l+r)/2;
query.assign(m,0);
for (int i = 1; i<=mid; i++){
query[parentedge[preorder[i]]]=1;
}
ll ans = ask(query);
if (ans<len*b){
l=mid+1;
} else {
r=mid-1;
}
}
int root = preorder[l];
// root at l, then search again
preorder.clear();
parentnode[root]=-1;
parentedge[root]=-1;
dfs(root,-1);
l = 0, r = n-1;
while (l<=r){
int mid = (l+r)/2;
query.assign(m,0);
for (int i = 1; i<=mid; i++){
query[parentedge[preorder[i]]]=1;
}
ll ans = ask(query);
if (ans<len*b){
l=mid+1;
} else {
r=mid-1;
}
}
//cout<<root<<' '<<preorder[l]<<'\n';
answer(root,preorder[l]);
}
Compilation message
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:36:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
36 | for (int i = 0; i<U.size(); i++){
| ~^~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
256 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
256 KB |
Output is correct |
4 |
Correct |
1 ms |
256 KB |
Output is correct |
5 |
Correct |
1 ms |
256 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
1 ms |
256 KB |
Output is correct |
8 |
Correct |
1 ms |
256 KB |
Output is correct |
9 |
Correct |
1 ms |
256 KB |
Output is correct |
10 |
Correct |
1 ms |
256 KB |
Output is correct |
11 |
Correct |
1 ms |
256 KB |
Output is correct |
12 |
Correct |
1 ms |
256 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
14 ms |
1280 KB |
Output is correct |
3 |
Correct |
190 ms |
8896 KB |
Output is correct |
4 |
Correct |
191 ms |
8992 KB |
Output is correct |
5 |
Correct |
166 ms |
8892 KB |
Output is correct |
6 |
Correct |
187 ms |
8824 KB |
Output is correct |
7 |
Correct |
192 ms |
8824 KB |
Output is correct |
8 |
Correct |
160 ms |
8828 KB |
Output is correct |
9 |
Correct |
190 ms |
8928 KB |
Output is correct |
10 |
Correct |
182 ms |
8916 KB |
Output is correct |
11 |
Correct |
197 ms |
10224 KB |
Output is correct |
12 |
Correct |
180 ms |
10964 KB |
Output is correct |
13 |
Correct |
176 ms |
10204 KB |
Output is correct |
14 |
Correct |
186 ms |
10276 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
2048 KB |
Output is correct |
2 |
Correct |
25 ms |
3832 KB |
Output is correct |
3 |
Correct |
36 ms |
5360 KB |
Output is correct |
4 |
Correct |
128 ms |
15308 KB |
Output is correct |
5 |
Correct |
121 ms |
15336 KB |
Output is correct |
6 |
Correct |
129 ms |
15324 KB |
Output is correct |
7 |
Correct |
125 ms |
15308 KB |
Output is correct |
8 |
Correct |
129 ms |
15400 KB |
Output is correct |
9 |
Correct |
128 ms |
15300 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
14 ms |
1280 KB |
Output is correct |
3 |
Correct |
137 ms |
7000 KB |
Output is correct |
4 |
Correct |
171 ms |
8820 KB |
Output is correct |
5 |
Correct |
174 ms |
8896 KB |
Output is correct |
6 |
Correct |
188 ms |
8824 KB |
Output is correct |
7 |
Correct |
168 ms |
8820 KB |
Output is correct |
8 |
Correct |
186 ms |
8880 KB |
Output is correct |
9 |
Correct |
193 ms |
8820 KB |
Output is correct |
10 |
Correct |
169 ms |
8952 KB |
Output is correct |
11 |
Correct |
198 ms |
9512 KB |
Output is correct |
12 |
Correct |
194 ms |
10952 KB |
Output is correct |
13 |
Correct |
192 ms |
10308 KB |
Output is correct |
14 |
Correct |
190 ms |
10788 KB |
Output is correct |
15 |
Correct |
166 ms |
8840 KB |
Output is correct |
16 |
Correct |
145 ms |
8840 KB |
Output is correct |
17 |
Correct |
191 ms |
10472 KB |
Output is correct |
18 |
Correct |
193 ms |
10540 KB |
Output is correct |
19 |
Correct |
180 ms |
8836 KB |
Output is correct |
20 |
Correct |
188 ms |
11500 KB |
Output is correct |
21 |
Correct |
140 ms |
9008 KB |
Output is correct |
22 |
Correct |
153 ms |
9008 KB |
Output is correct |
23 |
Correct |
156 ms |
9040 KB |
Output is correct |
24 |
Correct |
197 ms |
9932 KB |
Output is correct |
25 |
Correct |
182 ms |
14656 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
316 ms |
262148 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
289 ms |
262148 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |