Submission #1272376

#	Time	Username	Problem	Language	Result	Execution time	Memory
1272376		sasde	Watching (JOI13_watching)	C++20	100 / 100	137 ms	580 KiB

watching

#include<bits/stdc++.h>
using namespace std;
bool M1;
#define PI 3.14159265358979323846
#define sz(a) (int)a.size()
#define all(x) x.begin(),x.end()
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define se second
#define fi first
#define ffi fi.fi
#define sfi se.fi
#define sse se.se
#define fse fi.se
#define lt(i, c, d) for(int i = c; i <= d; ++i)
#define fl(i, c, d) for(int i = d; i >= c; --i)
#define pb push_back
#define emb emplace_back
#define emf emplace_front
#define em emplace
#define look_memory cerr<<abs(&M2-&M1)/1024.0/1024<<'\n'
#define look_time   cerr << "TIME : " << clock() * 0.001 << "s" <<'\n'
const int N=2e3+5,lg=30,mod=998244353;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int u,int v){
 return u+rd()%(v-u+1);
}
int dx[]={1,0,-1,0,1,1,-1,-1};
int dy[]={0,-1,0,1,1,-1,1,-1};
int node,a[N],p,q;
int dp[N],dpcur[N];
bool check(int mid){
  for(int i=1,j=1;i<=node;++i){
    while(a[i]-a[j]+1>mid)++j;
    dp[i]=dp[j-1]+1;
  }
  if(dp[node]<=p)return true;
  for(int _=1;_<=q;++_){
    int jp=1,jq=1;
    for(int i=1;i<=node;++i){
      while(a[i]-a[jp]+1>mid)++jp;
      while(a[i]-a[jq]+1>mid*2)++jq;
      dpcur[i]=dp[jq-1];
      dpcur[i]=min(dpcur[i],dpcur[jp-1]+1);
    }
    // for(int i=1;i<=node;++i)cout <<dpcur[i]<<" ";cout<<'\n';
    if(dpcur[node]<=p)return true;
    for(int i=1;i<=node;++i)dp[i]=dpcur[i];
  }

  return false;
}
bool M2;
void solve(){
  cin >> node >> p >> q;
  if(p+q>=node){
    cout <<1;
    return;
  }
	for(int i=1;i<=node;++i){
    cin >> a[i];
  }
  sort(a+1,a+1+node);
  int l=1,r=1e9,res=1;
  while(l<=r){
    int mid=(r+l)>>1;
    if(check(mid)){
      r=mid-1;
      res=mid;
    }
    else l=mid+1;
  }

  cout << res;
}
main()
{
  srand(time(0));
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    #define task "paleta"
    if(fopen(task".inp","r")){
      freopen(task".inp","r",stdin);
      freopen(task".out","w",stdout);
    }
    int t=1;
    solve();cout<<'\n';
look_memory;
look_time;
}

Compilation message (stderr)

watching.cpp:77:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   77 | main()
      | ^~~~
watching.cpp: In function 'int main()':
watching.cpp:85:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |       freopen(task".inp","r",stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
watching.cpp:86:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |       freopen(task".out","w",stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 50 / 50
• Subtask 2: 50 / 50