#include <iostream>
#include <map>
#include <set>
using namespace std;
 
struct shape {
 
	int x;
};
 
 
 
int main() {
	cout.setf(std::ios::boolalpha);
	shape arr[6] = {{1},{2},{3},{4},{5},{6}}; // some shapes
	map<shape*,set<shape*> > c; // although would consider smart pointers
	c[&arr[0]].insert(&arr[1]);
	c[&arr[1]].insert(&arr[0]);
 
	cout << "Shape 1 collides with 0: " << 	(bool)c[&arr[1]].count(&arr[0]) <<endl;
	cout << "Shape 1 collides with 2: " << 	(bool)c[&arr[1]].count(&arr[2]) <<endl;
	return 0;
}

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