Submission #934922

# Submission time Handle Problem Language Result Execution time Memory
934922 2024-02-28T07:53:02 Z sleepntsheep Highway Tolls (IOI18_highway) C++17
7 / 100
1500 ms 16008 KB
#include "highway.h"
#include<bits/stdc++.h>
using namespace std;

int n,m,a,b;std::vector<int>u,v;std::vector<std::pair<int,int>>g[90001];

int sub12(int src,int ban)
{
    vector<int>d(n,1e9),e(n,-1);
    queue<pair<int,int>>q; q.emplace(d[src]=0,src);
    while(q.size()){auto[c,u]=q.front();q.pop();for(auto[v,i]:g[u])if(ban-i&&d[v]>c+1)q.emplace(d[v]=c+1,v),e[v]=i;}

    long long need; {vector<int>qq(m,1);for(int i=0;i<n;++i)if(~e[i])qq[e[i]]=0;qq[ban]=0;need=ask(qq);}

    vector<int>c;
    for(int i=0;i<n;++i)if(d[i]<1e9)c.push_back(i);
    sort(c.begin(),c.end(),[&d](int i,int v){return d[i]<d[v];});

    int z=0,l=0,r=c.size()-1;
    while(l<=r){
        int y=(l+r)/2;
        vector<int>qq(m,1);
        qq[ban]=0;
        for(int i=1;i<=y;++i)if(~e[c[i]])qq[e[c[i]]]=0;
        if (ask(qq)==need)z=c[y],r=y-1;
        else l=y+1;
    }

    return z;
}

void sub1234(){
    long long need; {vector<int>qq(m,1); need=ask(qq);}
    auto dt = need / b;
    long long light = dt * a;

    int e1,l=0,r=m-1;
    while(l<=r) {
        int y=(l+r)/2;
        vector<int>qq(m);
        for(int i=0;i<=y;++i)qq[i]=1;
        if(ask(qq)>light)r=y-1,e1=y;
        else l=y+1;
    }

    int p=u[e1],q=v[e1],s=sub12(p,e1),t=sub12(q,e1);

    answer(s,t);
}

auto shortpath(int src){
    vector<int>d(n,1e9);
    queue<pair<int,int>>q;q.emplace(d[src]=0,src);
    while(q.size()){auto[c,u]=q.front();q.pop();for(auto [v,_]:g[u])if(d[v]>c+1)q.emplace(d[v]=c+1,v);}
    return d;
}

int tree(int rt,std::set<int>&S,std::set<int>&T,int e1){
    vector<int>d(n,1e9),e(n,-1);
    queue<pair<int,int>>q; q.emplace(d[rt]=0,rt);
    while(q.size()){auto[c,u]=q.front();q.pop();for(auto[v,i]:g[u])if(S.count(v)&&d[v]>c+1)q.emplace(d[v]=c+1,v),e[v]=i;}

    long long need;
    std::set<int>WhatisThis;
    {
        vector<int>qq(m,1);
        //for(int i=0;i<m;++i) if((S.count(u[i])&&S.count(v[i]))|| (T.count(u[i])||T.count(v[i]))); else qq[i]=1;
        for(int i=0;i<m;++i)
        {
            if((S.count(u[i])&&S.count(v[i])))qq[i]=0;
            if((T.count(u[i])&&T.count(v[i])))qq[i]=0;
        }
        qq[e1]=0;
        need=ask(qq);
    }

    vector<int>c;
    for(int i=0;i<n;++i)if(~e[i])c.push_back(i);
    sort(c.begin(),c.end(),[&d](int i,int v){return d[i]<d[v];});

    //printf(" C is : ");for(int x : c)printf("%d ",x);puts("");

    int z=rt,l=0,r=c.size()-1;
    while(l<=r){
        int y=(l+r)/2;
        vector<int>qq(m,0);
        for(int i=0;i<m;++i){
            if(S.count(u[i])&&S.count(v[i]))qq[i]=1;
            else if (T.count(v[i])&&T.count(u[i]))qq[i]=0;
            else qq[i]=1;
        }
        for(int i=0;i<=y;++i)if(~e[c[i]])qq[e[c[i]]]=0;
        qq[e1]=0;
        if (ask(qq)==need)z=c[y],r=y-1;
        else l=y+1;
    }

    return z;
}

void sub6()
{
    long long light; {vector<int>qq(m,0); light=ask(qq);}

    int e1,l=0,r=m-1;
    while(l<=r) {
        int y=(l+r)/2;
        vector<int>qq(m);
        for(int i=0;i<=y;++i)qq[i]=1;
        if(ask(qq)>light)r=y-1,e1=y;
        else l=y+1;
    }

    int U=u[e1],V=v[e1];

    auto du=shortpath(U),dv=shortpath(V);

    set<int>S,T;
    for(int i=0;i<n;++i)if(du[i]<dv[i])S.insert(i);else T.insert(i);

    int s = tree(U,S,T,e1);
    int t = tree(V,T,S,e1);
    //printf(" ST %d %d\n",s,t);
    answer(s,t);
}

void sub5(){
    int l=0,r=n-1;

    auto diffset = [&](vector<int>&grp){
        vector<int>qq(m);
        for(int i=0;i<m;++i)if(grp[u[i]]^grp[v[i]])qq[i]=0;else qq[i]=1;
        if(ask(qq)&1)return 1;return 0;
    };

    vector<int> gs,gt,grp(n);

    for(int b=0;b<=17;++b){
        for(int i=0;i<n;++i)
            grp[i]=(i>>b)&1;
        if(diffset(grp)) {break;}
    }

    for(int i=0;i<n;++i)if(grp[i])gt.push_back(i);else gs.push_back(i);

    while(gs.size()>1){
        vector<int>n1,n2,test(n);
        for(int i=0;i<gs.size()/2;++i)n1.push_back(gs[i]);
        for(int i=gs.size()/2;i<gs.size();++i)n2.push_back(gs[i]);
        for(int x:n1)test[x]=1;
        if(diffset(test))gs=n1;
        else gs=n2;
    }

    while(gt.size()>1){
        vector<int>n1,n2;
        for(int i=0;i<gt.size()/2;++i)n1.push_back(gt[i]);
        for(int i=gt.size()/2;i<gt.size();++i)n2.push_back(gt[i]);
        vector<int> test(n);for(int x:n1)test[x]=1;
        if(diffset(test))gt=n1;
        else gt=n2;
    }

    answer(gs[0],gt[0]);
}


void find_pair(int n_, std::vector<int> u_, std::vector<int> v_, int A_, int B_) {
    n=n_,u=u_,v=v_,a=A_,b=B_;m=u.size();
    for(int i=0;i<m;++i)g[u[i]].push_back({v[i],i}),g[v[i]].push_back({u[i],i});

    return sub6();
    if(a==1&&b==2)return sub5();
    sub1234();

}

Compilation message

highway.cpp: In lambda function:
highway.cpp:133:9: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  133 |         if(ask(qq)&1)return 1;return 0;
      |         ^~
highway.cpp:133:31: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  133 |         if(ask(qq)&1)return 1;return 0;
      |                               ^~~~~~
highway.cpp: In function 'void sub5()':
highway.cpp:148:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  148 |         for(int i=0;i<gs.size()/2;++i)n1.push_back(gs[i]);
      |                     ~^~~~~~~~~~~~
highway.cpp:149:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  149 |         for(int i=gs.size()/2;i<gs.size();++i)n2.push_back(gs[i]);
      |                               ~^~~~~~~~~~
highway.cpp:157:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  157 |         for(int i=0;i<gt.size()/2;++i)n1.push_back(gt[i]);
      |                     ~^~~~~~~~~~~~
highway.cpp:158:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  158 |         for(int i=gt.size()/2;i<gt.size();++i)n2.push_back(gt[i]);
      |                               ~^~~~~~~~~~
highway.cpp:128:9: warning: unused variable 'l' [-Wunused-variable]
  128 |     int l=0,r=n-1;
      |         ^
highway.cpp:128:13: warning: unused variable 'r' [-Wunused-variable]
  128 |     int l=0,r=n-1;
      |             ^
highway.cpp: In function 'void sub6()':
highway.cpp:114:15: warning: 'e1' may be used uninitialized in this function [-Wmaybe-uninitialized]
  114 |     int U=u[e1],V=v[e1];
      |               ^
highway.cpp: In function 'void sub1234()':
highway.cpp:46:15: warning: 'e1' may be used uninitialized in this function [-Wmaybe-uninitialized]
   46 |     int p=u[e1],q=v[e1],s=sub12(p,e1),t=sub12(q,e1);
      |               ^
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 2560 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 4 ms 2620 KB Output is correct
2 Correct 49 ms 3892 KB Output is correct
3 Correct 867 ms 14592 KB Output is correct
4 Correct 1143 ms 15056 KB Output is correct
5 Correct 1103 ms 14588 KB Output is correct
6 Correct 916 ms 14596 KB Output is correct
7 Correct 1190 ms 14840 KB Output is correct
8 Correct 1092 ms 14840 KB Output is correct
9 Correct 885 ms 14588 KB Output is correct
10 Correct 986 ms 14824 KB Output is correct
11 Correct 1330 ms 14424 KB Output is correct
12 Correct 1362 ms 14144 KB Output is correct
13 Correct 1329 ms 14460 KB Output is correct
14 Correct 1350 ms 14188 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 39 ms 3800 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 2612 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 74 ms 3932 KB Output is correct
2 Correct 78 ms 3964 KB Output is correct
3 Correct 1285 ms 14980 KB Output is correct
4 Execution timed out 1643 ms 16008 KB Time limit exceeded
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 82 ms 3892 KB Output is correct
2 Correct 82 ms 3960 KB Output is correct
3 Execution timed out 1551 ms 15300 KB Time limit exceeded
4 Halted 0 ms 0 KB -