diff --git a/examples/spgemm_helpers.hpp b/examples/spgemm_helpers.hpp
index 362fef6..243f9c2 100644
--- a/examples/spgemm_helpers.hpp
+++ b/examples/spgemm_helpers.hpp
@@ -52,7 +52,8 @@
     std::cout << "Runtime: " << runtime << std::endl;                          \
     std::cout << "Iterations: " << n_iter << std::endl;                        \
                                                                                \
-    long flops_per_iter = (result_nnz) * SPGEMM_FLOPS_PER_NZ;                  \
+    long flops_per_iter =                                                      \
+        static_cast<long long>(result_nnz) * SPGEMM_FLOPS_PER_NZ;              \
     double iter_per_second = n_iter / runtime;                                 \
                                                                                \
     std::cout << "Performance: " << flops_per_iter * iter_per_second * F_TO_GF \