Submission #941494

#	Time	Username	Problem	Language	Result	Execution time	Memory
941494		dwuy	Balloons (CEOI11_bal)	C++14	100 / 100	644 ms	13652 KiB

bal

#include <bits/stdc++.h>

#define fastIO ios_base::sync_with_stdio(false); cin.tie(NULL)
#define file(a) freopen(a".inp","r",stdin); freopen(a".out", "w",stdout)
#define fi first
#define se second
#define endl "\n"
#define len(s) int32_t(s.length())
#define MASK(k)(1LL<<(k))
#define TASK "test"
#define int long long
#define double long double

using namespace std;

typedef tuple<int, int, int> tpiii;
typedef pair<double, double> pdd;
typedef pair<int, int> pii;
typedef long long ll;

const long long OO = 1e18;
const int MOD = 1e9 + 7;
const int INF = 1e9;
const int MX = 200005;

int n;
pdd a[MX];
pdd v[MX];

void nhap(){
    cin >> n;
    for(int i=1; i<=n; i++) cin >> a[i].fi >> a[i].se;
}

double sqr(double x){
    return x*x;
}

double euler(pdd a, pdd b){
    return sqrt(sqr(a.fi - b.fi) + sqr(a.se - b.se));
}

double dis(pdd ball, double p){
    double lo=0, hi=INF;
    for(int t=0; t<65; t++){
        double mid = (lo+hi)/2;
        if(euler(ball, {p, mid}) >= mid + ball.se) lo = mid;
        else hi = mid;
    }
    return (lo + hi)/2;
}

void solve(){   
    stack<pdd> v;
    for(int i=1; i<=n; i++){
        double val = a[i].se;
        while(v.size()){
            val = min({val, dis(v.top(), a[i].fi)});
            if(val >= v.top().se) v.pop();
            else break;
        }
        v.push({a[i].fi, val});
        cout << fixed << setprecision(3) << val << '\n';
    }
}

int32_t main(){
    fastIO;
    //file(TASK);

    nhap();
    solve();

    return 0;
}

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