diff --git a/cxxmph/trigraph_test.cc b/cxxmph/trigraph_test.cc
new file mode 100644
index 0000000..6220138
--- /dev/null
+++ b/cxxmph/trigraph_test.cc
@@ -0,0 +1,22 @@
+#include <cassert>
+
+#include "trigraph.h"
+
+using cxxmph::TriGraph;
+
+int main(int argc, char** argv) {
+  TriGraph g(4, 2);
+  g.AddEdge(TriGraph::Edge(0, 1, 2));
+  g.AddEdge(TriGraph::Edge(1, 3, 2));
+  assert(g.vertex_degree()[0] == 1);
+  assert(g.vertex_degree()[1] == 2);
+  assert(g.vertex_degree()[2] == 2);
+  assert(g.vertex_degree()[3] == 1);
+  g.RemoveEdge(0);
+  assert(g.vertex_degree()[0] == 0);
+  assert(g.vertex_degree()[1] == 1);
+  assert(g.vertex_degree()[2] == 1);
+  assert(g.vertex_degree()[3] == 1);
+  std::vector<TriGraph::Edge> edges;
+  g.ExtractEdgesAndClear(&edges);
+}