Submission #676437

#	Time	Username	Problem	Language	Result	Execution time	Memory
676437		smirichto	Balloons (CEOI11_bal)	C++17	20 / 100	704 ms	10792 KiB

bal

#include<bits/stdc++.h>
using namespace std;
typedef long long ll ;
typedef long double ld ;
#define FAST ios::sync_with_stdio(0), cin.tie(0),cout.tie(0)
#define pb push_back
#define pi pair<int , int>
#define pll pair<ll,ll>
#define yes cout<<"Yes"<<endl;
#define no cout<<"No"<<endl;
#define firsst cout<<"First"<<endl;
#define seconnd cout<<"Second"<<endl;
#define tiie cout<<"Tie"<<endl;
#define fr(i,a,b) for(ll i = a;i < (ll)b;i++)
#define rfr(i,a,b) for(ll i = a;i > (ll)b;i--)
#define F first
#define S second
#define all(x) (x).begin(), (x).end()
#define alll(x) ((x).begin()+1), (x).end()
#define MOD mod
#define endl '\n'
//#define uid(a, b) uniform_ll_distribution<ll>(a, b)(rng)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll mod = 2019201997  ;
void io(){ios::sync_with_stdio(false) ;cin.tie(NULL) ;
freopen("walk.in","r",stdin) ;freopen("walk.out","w",stdout) ;
}
void dbg(vector<ll> tab){for(auto it : tab) cout<<it<<" ";cout<<endl;}
void dbgg(pi p){cout<<p.F<<" "<<p.S<<endl;}
void dbgpi(vector<pi> tab){for(auto it : tab) dbgg(it) ;}
template<class T> bool ckmax(T& a, const T& b){return a <= b ? a = b, 1 : 0;}
template<class T> bool ckmin(T& a, const T& b){return a >= b ? a = b, 1 : 0;}
template<class T> void add(T& a, const T& b){a = a + b ; if(a>mod) a-= mod ;}
void nop(){cout<<-1<<endl;return;}

const ll N = 1e3+5 ;

ld sq(ld x){
    return x*x ;
}

ld dist(ld x , ld y , ld xx , ld yy)
{
    return sqrtl(sq(x-xx) + sq(y-yy)) ;
}


void solve()
{
    int n ; cin>>n ;
    vector<ld> x(n+1) , r(n+1) ;
    for(int i = 1 ; i<=n ; i++){
        cin>>x[i]>>r[i] ;
    }
    ld ppi = acos(-1) ;
    cout<<fixed<<setprecision(3);
    cout<<r[1]<<endl;
    ld lst =  r[1]  , xlst = x[1];
    for(int i =2 ; i<=n ; i++){

        ld l = 0 , rr = r[i] ;
        ld p = l ;
        int k = 100 ;
        while(k--){
            ld md = (l+rr)/2 ;
            if(lst + md <= dist(xlst , lst , x[i] , md)){
                p = md ;
                l = md ;
            }
            else rr = md ;
        }
        cout<<p<<endl;
        if(x[i] + p>xlst + lst){
            xlst = x[i] ;
            lst = p ;
        }

    }

}

int main()
{
//    io() ;
    ll tt = 1 ;
//    cin>>tt ;
    while(tt--) solve() ;
    return 0 ;
}

Compilation message (stderr)

bal.cpp: In function 'void solve()':
bal.cpp:55:8: warning: unused variable 'ppi' [-Wunused-variable]
   55 |     ld ppi = acos(-1) ;
      |        ^~~
bal.cpp: In function 'void io()':
bal.cpp:26:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 | freopen("walk.in","r",stdin) ;freopen("walk.out","w",stdout) ;
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
bal.cpp:26:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 | freopen("walk.in","r",stdin) ;freopen("walk.out","w",stdout) ;
      |                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10