#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T> using Tree = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
using tint = long long;
using ld = long double;
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
using pi = pair<int,int>;
using pl = pair<tint,tint>;
using vi = vector<int>;
using vs = vector<string>;
using vl = vector<tint>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vvi = vector<vi>;
using vvl = vector<vl>;
using vb = vector<bool>;
using vvb = vector<vb>;
#define pb push_back
#define pf push_front
#define rsz resize
#define all(x) begin(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define ins insert
#define f first
#define s second
#define mp make_pair
#define DBG(x) cerr << #x << " = " << x << endl;
const int MOD = 1e9+7;
const int mod = 998244353;
const int MX = 2e5+5;
const tint INF = 1e18;
const int inf = 1e9;
const ld PI = acos(ld(-1));
const double eps = 1e-9;
const int dx[4] = {1, -1, 0, 0};
const int dy[4] = {0, 0, 1, -1};
template<class T> void remDup(vector<T> &v){
sort(all(v)); v.erase(unique(all(v)),end(v));
}
template<class T> bool ckmin(T& a, const T& b) {
return b < a ? a = b, 1 : 0;
}
template<class T> bool ckmax(T& a, const T& b) {
return a < b ? a = b, 1 : 0;
}
bool valid(int x, int y, int n, int m){
return (0<=x && x<n && 0<=y && y<m);
}
int cdiv(int a, int b) { return a/b+((a^b)>0&&a%b); } //redondea p arriba
int fdiv(int a, int b) { return a/b-((a^b)<0&&a%b); } //redondea p abajo
void NACHO(string name = ""){
ios_base::sync_with_stdio(0); cin.tie(0);
if(sz(name)){
freopen((name+".in").c_str(), "r", stdin);
freopen((name+".out").c_str(), "w", stdout);
}
}
pair<double, double> a[MX];
double ret[MX];
int main(){
NACHO();
int n; cin >> n;
F0R(i, n) cin >> a[i].f >> a[i].s;
// two balloons centered at (x1, r1) and (x2, r2)
// touch if the distance between the centers equals
// r1 + r2.
// hence we have sqrt((x2-x1)^2+(r2-r1)^2) = r1+r2
// (x2-x1)^2+(r2-r1)^2 = (r1+r2)^2
// (x2-x1)^2 = 4r1r2
// r2 = (x2-x1)^2/4r1
// furthermore, if balloons (x1, r1) and (x2, r2)
// have x1 < x2 and r1 < r2, then ballon 1 is useless
// as ballon 2 will always limit us more.
// therefore we mantain a stack with the property
// that radius are non increasing.
stack<pair<int, double>> st;
st.push(mp(a[0].f, a[0].s));
ret[0] = a[0].s;
FOR(i, 1, n){
ret[i] = a[i].s;
while(sz(st)){
ckmin(ret[i], double((a[i].f - st.top().f) * (a[i].f - st.top().f) / (4 * st.top().s)));
if(ret[i] >= st.top().s) st.pop();
else break;
}
st.push(mp(a[i].f, ret[i]));
}
F0R(i, n){
cout << fixed << setprecision(3) << ret[i] << "\n";
}
}
Compilation message
bal.cpp: In function 'void NACHO(std::string)':
bal.cpp:76:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
76 | freopen((name+".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bal.cpp:77:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
77 | freopen((name+".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
204 KB |
10 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
332 KB |
2 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
344 KB |
505 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
372 KB |
2000 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
19 ms |
1128 KB |
20000 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
49 ms |
2756 KB |
50000 numbers |
| 2 |
Correct |
51 ms |
2736 KB |
49912 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
103 ms |
5092 KB |
100000 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
128 ms |
5784 KB |
115362 numbers |
| 2 |
Correct |
110 ms |
6120 KB |
119971 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
172 ms |
7336 KB |
154271 numbers |
| 2 |
Correct |
185 ms |
10012 KB |
200000 numbers |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
196 ms |
8556 KB |
200000 numbers |
| 2 |
Correct |
183 ms |
10080 KB |
199945 numbers |
