make 'examples' plural

examples/group.cpp

@@ -0,0 +1,34 @@
+#include <iostream>
+
+#include <tc/solver.hpp>
+#include <tc/groups.hpp>
+
+int main() {
+    constexpr unsigned int Rank = 5;
+    constexpr unsigned int SRank = 3;
+
+    tc::Group<Rank> group = tc::schlafli<Rank>({5, 3, 2, 3});
+//    tc::Group<Rank> group = tc::group::E<Rank>();
+
+    tc::SubGroups<Rank, SRank> subs = tc::subgroups<Rank, SRank>(group);
+
+    std::cout << "Group " << group.name << " (" << subs.size() << " subgroups)" << std::endl;
+    std::cout << group << std::endl;
+
+    for (const auto &sub: subs) {
+        for (int i = 0; i < SRank; ++i) {
+            for (int j = 0; j < SRank; ++j) {
+                auto sub_mult = sub(i, j);
+                auto src_mult = group(sub.gens(i), sub.gens(j));
+
+                if (sub_mult != src_mult) {
+                    std::cout << "Incorrect subgroup " << sub.name << std::endl;
+                    std::cout << sub << std::endl;
+                    return 1;
+                }
+            }
+        }
+    }
+
+    return 0;
+}