Submission #1055161

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1055161	2024-08-12T15:01:06 Z	Ahmed57	Highway Tolls (IOI18_highway)	C++17	18 / 100	205 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 = -1;
    for(int i = 0;i<v.size();i++){
        if(v[i].first==ans2&&l==-1)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;
        }
        if(ask(as)==len+(dep[a]-ans2+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	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	4724 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	93 ms	13692 KB	Output is correct
4	Correct	71 ms	13724 KB	Output is correct
5	Correct	79 ms	13856 KB	Output is correct
6	Correct	71 ms	13692 KB	Output is correct
7	Correct	84 ms	13852 KB	Output is correct
8	Correct	74 ms	13696 KB	Output is correct
9	Correct	86 ms	13856 KB	Output is correct
10	Correct	75 ms	13732 KB	Output is correct
11	Correct	80 ms	14856 KB	Output is correct
12	Correct	84 ms	15288 KB	Output is correct
13	Correct	96 ms	14984 KB	Output is correct
14	Correct	84 ms	14456 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	19 ms	8720 KB	Output is correct
4	Correct	61 ms	17584 KB	Output is correct
5	Correct	61 ms	17544 KB	Output is correct
6	Correct	61 ms	17556 KB	Output is correct
7	Correct	58 ms	17584 KB	Output is correct
8	Correct	61 ms	17556 KB	Output is correct
9	Correct	63 ms	17600 KB	Output is correct