Submission #1149351

#	Time	Username	Problem	Language	Result	Execution time	Memory
1149351		ByeWorld	Mobile (BOI12_mobile)	C++20	100 / 100	416 ms	31760 KiB

mobile

#include <bits/stdc++.h>
#define int long long
#define ll long long
#define pb push_back
#define fi first
#define se second
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<char,char> pcc;
typedef pair<pii,int> ipii;
typedef pair<pii,pii> ipiii;
const int MAXN = 1e6+10;
const int SQRT = 300;
const int MAXA = 50;
const int LOG = 20;
const int INF = 1e12+10;
const ld EPS = 1e-6;
const int MOD = 998244353;
int sum(int a, int b){ return (a+b)%MOD; }
void chsum(int &a, int b){ a = (a+b)%MOD; }
void chsub(int &a, int b){ a = (a+MOD-b)%MOD; }
int mul(int a, int b){ return (a*b)%MOD; }
void chmul(int &a, int b){ a = (a*b)%MOD; }
void chmn(int &a, int b){ a = min(a, b); }
void chmx(int &a, int b){ a = max(a, b); }

int n;
ld len, x[MAXN], y[MAXN];

bool cek(ld mid){
    ld mx = 0;
    for(int i=1; i<=n; i++){ 
        if(abs(y[i]) > mid) continue;
        ld dis = sqrt(mid*mid - y[i]*y[i]);
        if(x[i]-dis <= mx) mx = max(mx, x[i]+dis);
        if(mx >= len) return 1;
    }
    return 0;
}
signed main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin>>n>>len;
    for(int i=1; i<=n; i++) cin>>x[i]>>y[i];
        // cout << cek(5) <<"cek\n";
    // return 0;
    ld l=0, r=2e9, mid=0, cnt=0;
    while(r-l>=1e-4){
        mid = (l+r)/2;
        if(cek(mid)) cnt = mid, r = mid;
        else l = mid;
    }
    cout << fixed << setprecision(10) << cnt << '\n';
}

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5