Submission #1055174

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1055174	2024-08-12T15:04:18 Z	Ahmed57	Highway Tolls (IOI18_highway)	C++17	18 / 100	188 ms	262144 KB

highway

#include "bits/stdc++.h"
#include "highway.h"

using namespace std;
#define int long long
pair<int,int> p[100001];
int dep[100001];
vector<pair<int,int>> adj[100001];
void dfs(int i,int pr,int id){
    dep[i] = dep[pr]+1;
    p[i] = {pr,id};
    for(auto j:adj[i]){
        if(j.first==pr)continue;
        dfs(j.first,i,j.second);
    }
}

void find_pair(int32_t N, vector<int32_t> U, vector<int32_t> V, int32_t A, int32_t B){
    int m = U.size();
    vector<int32_t> as(m,0);
    vector<int32_t> as2(m,1);
    int len = ask(as);
    int len2 = ask(as2);
    for(int i = 0;i<U.size();i++){
        adj[U[i]].push_back({V[i],i});
        adj[V[i]].push_back({U[i],i});
    }
    dfs(0,0,-1);
    vector<pair<int,int>> v;
    for(int i = 0;i<N;i++){
        v.push_back({dep[i],i});
    }
    sort(v.begin(),v.end());
    reverse(v.begin(),v.end());
    int l = 0 , r = v.size()-2 , ans = 0;
    while(l<=r){
        int mid = (l+r)/2;
        vector<int32_t> as(m,0);
        for(int i = 0;i<=mid;i++){
            as[p[v[i].second].second] = 1;
        }
        if(ask(as)!=len){
            ans = mid;
            r = mid-1;
        }else l = mid+1;
    }
    int a = v[ans].second;
    l = 2 , r = dep[a] ;int ans2 = -1; 
    while(l<=r){
        int mid = (l+r)/2;
        vector<int32_t> as(m,0);
        for(int i = 0;i<N;i++){
            if(dep[i]>=mid){
                as[p[i].second] =1 ;
            }
        }
        int na = ask(as);
        if(na==len2){
            ans2 = mid;
            l = mid+1;
        }else r = mid-1;
    }
    ans2--;
    if((dep[a]-ans2)*A==len){
        int x = len/A;
        int b = a;
        while(x--){
            b = p[b].first;
        }
        answer(a,b);
        return ;
    }
    vector<int> lol;
    l = 0;
    for(int i = 0;i<v.size();i++){
        if(v[i].second==a)l = i;
        if(v[i].first>ans2)r = i;
    }   
    int ans3 = 0;
    while(l<=r){
        int mid = (l+r)/2;
        vector<int32_t> as(m,0);
        for(int i = 0;i<=mid;i++){
            as[p[v[i].second].second] = 1;
        }
        int f = a;
        while(dep[f]>v[mid].first)f = p[f].first;
        as[p[f].second] = 1;
        if(ask(as)==len+(dep[a]-v[mid].second)*(B-A)+(B-A)){
            ans3 = mid;
            r = mid-1;
        }else l = mid+1;
    }
    int b = v[ans3].second;
    answer(a,b);
}

Compilation message

highway.cpp: In function 'void find_pair(int32_t, std::vector<int>, std::vector<int>, int32_t, int32_t)':
highway.cpp:24:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     for(int i = 0;i<U.size();i++){
      |                   ~^~~~~~~~~
highway.cpp:75:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |     for(int i = 0;i<v.size();i++){
      |                   ~^~~~~~~~~

Subtask #1
5.0 / 5.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4696 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4696 KB	Output is correct
4	Correct	1 ms	4696 KB	Output is correct
5	Correct	1 ms	4696 KB	Output is correct
6	Correct	1 ms	4696 KB	Output is correct
7	Correct	1 ms	4696 KB	Output is correct
8	Correct	1 ms	4696 KB	Output is correct
9	Correct	1 ms	4696 KB	Output is correct
10	Correct	1 ms	4696 KB	Output is correct
11	Correct	1 ms	4696 KB	Output is correct
12	Correct	1 ms	4696 KB	Output is correct

Subtask #2
7.0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4696 KB	Output is correct
2	Correct	7 ms	5720 KB	Output is correct
3	Correct	75 ms	13692 KB	Output is correct
4	Correct	75 ms	13744 KB	Output is correct
5	Correct	73 ms	13744 KB	Output is correct
6	Correct	69 ms	13712 KB	Output is correct
7	Correct	68 ms	13712 KB	Output is correct
8	Correct	78 ms	13832 KB	Output is correct
9	Correct	68 ms	13744 KB	Output is correct
10	Correct	73 ms	13696 KB	Output is correct
11	Correct	73 ms	15024 KB	Output is correct
12	Correct	79 ms	15280 KB	Output is correct
13	Correct	80 ms	15040 KB	Output is correct
14	Correct	76 ms	14460 KB	Output is correct

Subtask #3
6.0 / 6.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	7 ms	6232 KB	Output is correct
2	Correct	14 ms	7644 KB	Output is correct
3	Correct	19 ms	8656 KB	Output is correct
4	Correct	73 ms	17584 KB	Output is correct
5	Correct	65 ms	17548 KB	Output is correct
6	Correct	56 ms	17584 KB	Output is correct
7	Correct	59 ms	17584 KB	Output is correct
8	Correct	61 ms	17556 KB	Output is correct
9	Correct	62 ms	17584 KB	Output is correct