modified coxeter notation parsing

tc/src/langtest.cpp

@@ -0,0 +1,39 @@
+#include <iostream>
+
+#include <tc/group.hpp>
+#include <tc/groups.hpp>
+
+int main() {
+    std::vector<std::string> symbols = {
+        "5 3 3",
+        "5 (3 3)",
+        "[5 3 3]",
+        "[4 3 [3 5] 3]",
+        "{3 4 5 6 7 8 9}",
+        "3 {3 3 [4] 3} 5",
+        "5 * 3",
+        "5 * [3]",
+        "5 * {2 3}",
+        "5 * [3 2]",
+        "(5 2) * [3 2]",
+        "4 [3 * [2 3]] 5",
+        "{3 * 3} [4] [5]",
+    };
+
+    for (const auto &symbol: symbols) {
+        auto group = tc::coxeter(symbol);
+        
+        std::cout << "'" << symbol << "'" << std::endl;
+
+        for (int i = 0; i < group.ngens; ++i) {
+            for (int j = 0; j < group.ngens; ++j) {
+                std::cout << group.get(i, j) << " ";
+            }
+            std::cout << std::endl;
+        }
+        
+        std::cout << "===========================" << std::endl;
+    }
+    
+    return EXIT_SUCCESS;
+}