#include <iostream>
#include <cmath>
#include <cfloat>
#include <algorithm>
#include <cstdlib>
#include <fstream>

using namespace std;

#define FNAME "myacm.txt"
#define cin fin

ifstream fin(FNAME);

#define EPS FLT_EPSILON
#define NMONUMENT_MAX 15
#define deq( a, b ) (fabs((a) - (b)) < EPS)

#define PARALLEL 0
#define LEFT 1
#define RIGHT 2

class Monument {
public:
	char label;
	int x, y;

	Monument() {}
	Monument( int x, int y ) : x(x), y(y) {}

	bool operator < ( const Monument &m ) const {
		return (label < m.label);
	}

};

int nmonument;
Monument M[NMONUMENT_MAX];

int direction( const Monument &p, const Monument &q, const Monument &t ) {
	const double cp = (q.x-p.x)*(t.y-p.y) - (t.x-p.x)*(q.y-p.y);

	if ( deq(cp, 0) ) return PARALLEL;
	return (cp > 0)? LEFT : RIGHT;
}

bool isValid( int i, int j, int k ) {
	for ( int n = 0; n < nmonument; n++ ) {
		if ( n == i || n == j || n == k ) continue;

		const int ij = direction(M[i], M[j], M[n]);
		const int jk = direction(M[j], M[k], M[n]);
		const int ki = direction(M[k], M[i], M[n]);

		if ( ij != PARALLEL && ij != direction(M[i], M[j], M[k]) ) continue;
		if ( jk != PARALLEL && jk != direction(M[j], M[k], M[i]) ) continue;
		if ( ki != PARALLEL && ki != direction(M[k], M[i], M[j]) ) continue;
		return false;
	}

	return true;
}

int main() {
	while ( cin >> nmonument && nmonument != 0 ) {
		for ( int i = 0; i < nmonument; i++ ) cin >> M[i].label >> M[i].x >> M[i].y;
		sort(M, M+nmonument);

		int maxArea = -1;
		char labels[3];
		for ( int i = 0; i < nmonument; i++ )
			for ( int j = i+1; j < nmonument; j++ )
				for ( int k = j+1; k < nmonument; k++ ) {
					const int areadup = abs((M[k].y-M[i].y)*(M[j].x-M[i].x) - (M[j].y-M[i].y)*(M[k].x-M[i].x));

					if ( areadup > 0 && isValid(i, j, k) ) {
						if ( areadup <= maxArea ) continue;
						maxArea = areadup;
						labels[0] = M[i].label;
						labels[1] = M[j].label;
						labels[2] = M[k].label;
					}
				}

		cout << labels[0] << labels[1] << labels[2] << endl;
	}

	return 0;
}