Submission #643397

#	Time	Username	Problem	Language	Result	Execution time	Memory
643397		christinelynn	Martian DNA (BOI18_dna)	C++17	100 / 100	149 ms	25924 KiB

dna

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
const ll MOD=1e9+7;
using namespace std;
ll N,M,K,a[200005],point[200005];
vector <ll> vec[200005];
vector <pair<ll,ll> > pr[200005];
int main(){
  cin>>N>>M>>K;
  if(K<=10){
    for(int i=1;i<=N;i++){
      cin>>a[i];
      vec[a[i]].push_back(i);
    }
    bool ok=true;
    for(int i=1;i<=K;i++){
      ll x,y;
      cin>>x>>y;
  //    cout<<vec[x].size()<<' '<<y<<endl;
      if(vec[x].size()<y){
        ok=false;
      }
      else{
        for(int j=y-1;j<vec[x].size();j++){
          pr[i].push_back({vec[x][j-(y-1)],vec[x][j]});
        }
      }
    }
    if(!ok){
      cout<<"impossible"<<endl;
      return 0;
    }
    ll minn=1e18;
    for(int i=1;i<=N;i++){
      ll maks=0;
      bool ok=true;
      for(int j=1;j<=K;j++){
        ll l=0;
        ll r=pr[j].size()-1;
        ll ans=-1;
        while(l<=r){
          ll m=(l+r)/2;
          if(pr[j][m].fi>=i){
            ans=m;
            r=m-1;
          }
          else{
            l=m+1;
          }
        }
        if(ans==-1){
          ok=false;
          break;
        }
        maks=max(maks,pr[j][ans].se);
      }
      if(ok){
        minn=min(minn,maks-i+1);
      }
    }
    cout<<minn<<endl;
  }
  else{
    for(int i=1;i<=N;i++){
      cin>>a[i];
      vec[a[i]].push_back(i);
    }
    bool ok=true;
    for(int i=1;i<=K;i++){
      ll x,y;
      cin>>x>>y;
      if(vec[x].size()<y){
        ok=false;
      }
      else{
        for(int j=y-1;j<vec[x].size();j++){
          pr[i].push_back({vec[x][j-(y-1)],vec[x][j]});
        }
      }
    }
    if(!ok){
      cout<<"impossible"<<endl;
      return 0;
    }
    priority_queue <pair<pair<ll,ll>,ll>,vector<pair<pair<ll,ll>,ll> >,greater<pair<pair<ll,ll>,ll> > > pq;
    ll l=1e18;
    ll r=-1e18;
    for(int i=1;i<=K;i++){
      pq.push({{pr[i][0].fi,pr[i][0].se},i});
      l=min(l,pr[i][0].fi);
      r=max(r,pr[i][0].se);
      point[i]=0;
    }
    ll minn=r-l+1;
    while(true){
      ll x=pq.top().fi.fi;
      ll y=pq.top().fi.se;
      ll z=pq.top().se;
      pq.pop();
      if(point[z]==pr[z].size()-1){
        break;
      }
      point[z]++;
      pq.push({pr[z][point[z]],z});
      l=pq.top().fi.fi;
      r=max(r,pr[z][point[z]].se);
      minn=min(minn,r-l+1);
    }
    cout<<minn<<endl;
  }
}

Compilation message (stderr)

dna.cpp: In function 'int main()':
dna.cpp:23:23: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   23 |       if(vec[x].size()<y){
      |          ~~~~~~~~~~~~~^~
dna.cpp:27:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |         for(int j=y-1;j<vec[x].size();j++){
      |                       ~^~~~~~~~~~~~~~
dna.cpp:75:23: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   75 |       if(vec[x].size()<y){
      |          ~~~~~~~~~~~~~^~
dna.cpp:79:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |         for(int j=y-1;j<vec[x].size();j++){
      |                       ~^~~~~~~~~~~~~~
dna.cpp:103:18: 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]
  103 |       if(point[z]==pr[z].size()-1){
      |          ~~~~~~~~^~~~~~~~~~~~~~~~
dna.cpp:99:10: warning: unused variable 'x' [-Wunused-variable]
   99 |       ll x=pq.top().fi.fi;
      |          ^
dna.cpp:100:10: warning: unused variable 'y' [-Wunused-variable]
  100 |       ll y=pq.top().fi.se;
      |          ^

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 28 / 28
• Subtask 4: 32 / 32