Submission #1055179

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1055179	2024-08-12T15:05:26 Z	Ahmed57	Highway Tolls (IOI18_highway)	C++17	18 / 100	191 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+1)*(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	4692 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	2 ms	4696 KB	Output is correct
2	Correct	9 ms	5720 KB	Output is correct
3	Correct	76 ms	13696 KB	Output is correct
4	Correct	67 ms	13692 KB	Output is correct
5	Correct	72 ms	13744 KB	Output is correct
6	Correct	67 ms	13832 KB	Output is correct
7	Correct	69 ms	13944 KB	Output is correct
8	Correct	80 ms	13836 KB	Output is correct
9	Correct	72 ms	13744 KB	Output is correct
10	Correct	80 ms	13708 KB	Output is correct
11	Correct	92 ms	14972 KB	Output is correct
12	Correct	93 ms	15244 KB	Output is correct
13	Correct	90 ms	14992 KB	Output is correct
14	Correct	72 ms	14512 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	13 ms	7548 KB	Output is correct
3	Correct	21 ms	8656 KB	Output is correct
4	Correct	59 ms	17548 KB	Output is correct
5	Correct	63 ms	17672 KB	Output is correct
6	Correct	72 ms	17548 KB	Output is correct
7	Correct	59 ms	17584 KB	Output is correct
8	Correct	60 ms	17544 KB	Output is correct
9	Correct	59 ms	17584 KB	Output is correct