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#include<bits/stdc++.h> 
using namespace std; 
double pi = 3.1415; 
int c(float x, float y) 
{ 
double r = sqrt(x*x + y*y); 
double s = pi * r * r / 2; 
int numYear = (int)(s / 50);  
return numYear; 

} 
int main() 
{ 

int n; 
cin >> n; 
double a[n*2]; 
for(int i=0;i<2*n;i++) 
 cin>>a[i]; 

int y[n]; 
for(int i = 1; i <= n; i++) 
{ 
 y[i] = c(a[i], a[i+1]); 
 cout << "Property "<<i<<": This property will begin eroding in year "<< y[i] << "." << endl; 
} 
cout << "END OF OUTPUT." << endl; 

}