include iostream include vector include algorithm include cmath includ

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#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <iomanip>
using namespace std;
int n;
double eps = 1e-9;
struct C
{
int x;
int y;
int r;
};
vector<C> v(50);
vector<pair<double, bool> > q;
double F(double x)
{
q.clear();
pair<double,bool> temp;
for(int i = 0; i < n; i++)
{
if(fabs(x - v[i].x) < v[i].r)
{
temp.first = -sqrt(v[i].r*v[i].r - (v[i].x - x)*(v[i].x - x)) + v[i].y;
temp.second = true;
q.push_back(temp);
temp.first = sqrt(v[i].r*v[i].r - (v[i].x - x)*(v[i].x - x)) + v[i].y;
temp.second = false;
q.push_back(temp);
}
}
sort(q.begin(), q.end()); // здесь v.begin(), v.end из-за этого на компе кстати не запускался
int rang = 0;
double l, s = 0;
for(int i = 0; i < q.size(); i++)
{
if(q[i].second)
{
if(rang == 0)
l = q[i].first;
rang++;
}
else rang--;
if(i !=0 && rang == 0)
{
s+= q[i].first - l;
}
}
return s;
}
double S(double a, double b)
{
return (F(a) + F(b) + 4*F((a+b)/2))*(b-a)/6;
}
double Square(double a, double b)
{
double mid = (a+b)/2;
double t1 = S(a,b);
double t2 = S(a, mid);
double t3 = S(mid, b);
if(fabs(S(a,b) - (S(a, mid) + S(mid,b))) < eps)
return S(a,b);
else
return (Square(a, mid) + Square(mid,b)); //здесь было S(a,mid)
}
int main()
{
cin >> n;
double l,r;
cin >> v[0].x >> v[0].y >> v[0].r;
l = v[0].x - v[0].r;
r = v[0].x + v[0].r;
for(int i = 1; i < n; i++)
{
cin >> v[i].x >> v[i].y >> v[i].r;
if(v[i].x - v[i].r < l)
l = v[i].x - v[i].r;
if(v[i].x + v[i].r > r)
r = v[i].x + v[i].r;
}
cout << fixed << setprecision(5) << Square(l,r) << endl;
return 0;
}