枚举
#include<iostream> #include<algorithm> using namespace std; struct point { char ss; int x, y; }; struct direction { char ul, ur, lr, ll; }; direction dir[100]; point p[30]; int sum; int cmp(point a, point b) { if (a.x != b.x) return a.x < b.x; else return a.y < b.y; } int cmp_re(direction a, direction b) { if (a.ul != b.ul) return a.ul < b.ul; else { if (a.ur != b.ur) return a.ur < b.ur; else { if (a.lr != b.lr) return a.lr < b.lr; else return a.ll < b.ll; } } } bool work(int n) { int i, j, k, l; for (i = 0; i < n; ++i) { for (j = i + 1; j < n; ++j) { if (p[i].x == p[j].x) { for (k = j + 1; k < n; ++k) { if (p[i].y == p[k].y) { for (l = k + 1; l < n; ++l) { if (p[j].y - p[i].y == p[l].y - p[k].y && p[k].x - p[i].x == p[l].x - p[j].x) { dir[sum].ul = p[j].ss, dir [sum].ur = p[l].ss; dir[sum].lr = p[k].ss, dir [sum].ll = p[i].ss; sum++; } } } } } } } if (!sum) return false; else return true; } int main() { int i, n, cas = 1; // freopen("t.txt","r",stdin); // freopen("out.txt","w",stdout); while (cin >> n && n) { for (i = 0; i < n; ++i) cin >> p[i].ss >> p[i].x >> p[i].y; sort(p, p + n, cmp); sum = 0; cout << "Point set " << cas++ << ":"; if (!work(n)) cout << " No rectangles" << endl; else { cout << endl; sort(dir, dir + sum, cmp_re); for (i = 0; i < sum; ++i) { cout << " " << dir[i].ul << dir[i].ur << dir[i].lr << dir[i].ll; if ((i + 1) % 10 == 0 && i + 1 < sum) cout << endl; } cout << endl; } } return 0; }