#include #include #include using namespace std; int y[10005]; int main() { int n,tmp; cin>>n; for(int i=1;i<=n;i++) { cin>>tmp>>y[i]; } sort(y+1,y+n+1); int mid; if(n%2==1) { mid=y[(n+1)/2]; } else { mid=(y[n/2]+y[n/2+1])/2; }

int sum=0;
for(int i=1;i<=n;i++)
{
	sum+=abs(y[i]-mid);
}
cout<<sum<<endl;
return 0;

}