oj.uz

Submission #494138

# Submission time Handle Problem Language Result Execution time Memory
494138 2021-12-14T12:46:09 Z PikaQ Mobile (BOI12_mobile) C++17
0 / 100
 4 ms 332 KB 
#include<bits/stdc++.h>
#define int ll
#define forn(i,n) for(int i=0;i<(n);i++)
#define Forn(i,n) for(int i=1;i<=(n);i++)
#define ll long long
#define pb push_back
#define F first
#define S second
#define lb lower_bound
#define ub upper_bound
#define vi vector<int>
#define vl vector<long long>
#define vpi vector<pair<int,int> >
#define pii pair<int,int>
#define pll pair<long long,long long>
#define mp make_pair
#define rz resize
#define all(p) p.begin(),p.end()
#define alr(p,q) p+1,p+q+1
#define ull unsigned long long
#define st0(p) memset((p),0,sizeof(p))
#define T(x) ((x)%2 ? s[(x)/2] : '.')
#define lowb(x) x&-x
#define ls(x) (x)*2
#define rs(x) (x)*2+1
using namespace std;

inline void USACO(string filename){
  freopen((filename+".in").c_str(),"r",stdin);
  freopen((filename+".out").c_str(),"w",stdout);
}

void debug() {cout << endl;}
template <class T, class ...U> void debug(T a, U ... b) { cout << a << " "; debug(b...);}
// template <class T> int max(T a, T ... b) { cout << a << " "; debug(b...);}
const int INF = 1e9+7;
const double eps = 1e-7;
const int N = 8e2+9;
int n;
double L;
#define pdd pair<double,double> 
vector<pdd> p;


bool check(double R){
  stack<pdd> sk;
  double cur = 0;
  for(auto &i : p){
    double dy = abs(i.S);
    if(dy > R) continue;
    double d = sqrt(R*R - dy*dy);
    double l = i.F -d,r = i.F +d;
    l = max((double)0,l),r = min(L,r);
    if(l <= cur) cur = max(cur,r);
  }
  return cur >= L;
}

void solve(){
  cin >> n >> L;
  p.rz(n);
  forn(i,n) cin >> p[i].F >> p[i].S;
  sort(all(p));
  double lo = 0,hi = 1e6;
  while(hi - lo > 1e-7){
    double mid = (lo+hi)/2;
    if(check(mid)) hi = mid;
    else lo = mid;
  }
  cout << fixed << setprecision(4) <<  hi << '\n';
}     



signed main(){
  // USACO("angry");
  cin.tie(0);
  cout.tie(0);
  ios_base::sync_with_stdio(0);

  #ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
  #endif

  // int t;
  // cin >> t;
  // while(t--)
    solve();
  return 0;
}

Compilation message

mobile.cpp: In function 'int main()':
mobile.cpp:82:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   82 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
mobile.cpp:83:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |     freopen("output.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 268 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #2
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #3
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #4
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #5
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #6
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #7
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #8
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #9
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #10
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #11
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #12
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #13
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #14
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #15
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #16
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #17
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #18
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 4 ms 328 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #19
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #20
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -

Subtask #21
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 332 KB Unexpected end of file - double expected
2 Halted 0 ms 0 KB -