Submission #1055204

# Submission time Handle Problem Language Result Execution time Memory
1055204 2024-08-12T15:22:40 Z Ahmed57 Highway Tolls (IOI18_highway) C++17
18 / 100
195 ms 262144 KB
#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;
    }
    assert(ans2!=-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 = -1;
    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].first+1)*(B-A)+(B-A)){
            ans3 = mid;
            r = mid-1;
        }else l = mid+1;
    }
    //assert(ans3!=-1);
    if(ans3==-1){
        int x = len/A;
        int b = a;
        while(x--){
            b = p[b].first;
        }
        answer(a,b);
        return ;
    }
    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:76:20: 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]
   76 |     for(int i = 0;i<v.size();i++){
      |                   ~^~~~~~~~~
# 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
# 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 71 ms 13688 KB Output is correct
4 Correct 78 ms 13688 KB Output is correct
5 Correct 71 ms 13744 KB Output is correct
6 Correct 68 ms 13820 KB Output is correct
7 Correct 64 ms 13744 KB Output is correct
8 Correct 72 ms 13744 KB Output is correct
9 Correct 72 ms 13740 KB Output is correct
10 Correct 73 ms 13744 KB Output is correct
11 Correct 77 ms 14928 KB Output is correct
12 Correct 91 ms 15240 KB Output is correct
13 Correct 77 ms 15024 KB Output is correct
14 Correct 80 ms 14416 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 7 ms 6232 KB Output is correct
2 Correct 16 ms 7708 KB Output is correct
3 Correct 19 ms 8644 KB Output is correct
4 Correct 63 ms 17584 KB Output is correct
5 Correct 59 ms 17588 KB Output is correct
6 Correct 61 ms 17584 KB Output is correct
7 Correct 60 ms 17584 KB Output is correct
8 Correct 59 ms 17528 KB Output is correct
9 Correct 57 ms 17584 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4696 KB Output is correct
2 Correct 8 ms 5824 KB Output is correct
3 Correct 60 ms 11956 KB Output is correct
4 Incorrect 82 ms 13744 KB Output is incorrect: {s, t} is wrong.
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 195 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 177 ms 262144 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -