С++ как сделать без массивов

#include
using namespace std;
int main() {
double coords[5][2] = {{1.3, 2.7},{-2.1, 4.3},{-3.7,-4.1},{2.5,-3.8},{0, -4.9}};
double r;
cout << "r?.. "; cin >> r;
double x, y, test;
for (int n = 0; n < 5; n++) {
x = coords[n][0];
y = coords[n][1];
test = sqrt(pow(x, 2) + pow(y, 2));
if (test <= r) cout << '(' << x << "; " << y << ") -> yes";
else cout << '(' << x << "; " << y << ") -> no";
cout << endl;
}
cin.get(); cin.get();
return 0;
}