static void /* column adjust for range -1 to 1 to a to b */
colshft(double a, double b, projUV **d, int n, int m) {
int k, j;
double fac, cnst;
cnst = 2. / (b - a);
fac = cnst;
for (j = 1; j < n; ++j) {
dmult(d[j], fac, m);
fac *= cnst;
}
cnst = .5 * (a + b);
for (j = 0; j <= n-2; ++j)
for (k = n - 2; k >= j; --k)
dadd(d[k], d[k+1], cnst, m);
}
int main()
{
int n;
bool flag;
double ans;
while (scanf("%d", &n) != EOF && n > 0) {
for (int i = 0; i < n; i++) {
scanf("%d%d%d", &p[i].x, &p[i].y, &p[i].z);
}
ans = 0;
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
for (int k = j + 1; k < n; k++) {
Point dn = xmult(p[j] - p[i], p[k] - p[i]);
ss = 0;
flag = true;
for (int t = 0; t < n; t++) {
s[t] = sign(dmult(dn, p[t] - p[i]));
if (s[t] != 0) {
if (ss == 0) {
ss = s[t];
}
else if (ss != s[t]) {
flag = false;
break;
}
}
}
if (flag) {
ans += abs(dn);
}
}
}
}
printf("%.0lf\n", ans / 2);
}
return 0;
}
double angle_sin(point3 l1,point3 l2,point3 s1,point3 s2,point3 s3)
{
return dmult(subt(l1,l2),pvec(s1,s2,s3))/vlen(subt(l1,l2))/vlen(pvec(s1,s2,s3));
}
double angle_sin(line3 l,plane3 s)
{
return dmult(subt(l.a,l.b),pvec(s))/vlen(subt(l.a,l.b))/vlen(pvec(s));
}
