2 files changed, 6 insertions, 5 deletions

diff --git a/lib/wolff.h b/lib/wolff.h
index 4839083..cec9ee3 100644
--- a/lib/wolff.h
+++ b/lib/wolff.h
@@ -27,7 +27,7 @@ typedef struct ll_tag {
 } ll_t;
 
 typedef struct {
-  int32_t nv;
+  uint32_t nv;
   double dH;
   int32_t dM;
 } cluster_t;
@@ -48,5 +48,5 @@ double hh(double th);
 
 double *get_bond_probs(double T, double H, ising_state_t *s);
 
-int32_t wolff_step(double T, double H, ising_state_t *s, gsl_rng *r, double *ps);
+uint32_t wolff_step(double T, double H, ising_state_t *s, gsl_rng *r, double *ps);
 
diff --git a/lib/wolff_tools.c b/lib/wolff_tools.c
index d361344..016e19b 100644
--- a/lib/wolff_tools.c
+++ b/lib/wolff_tools.c
@@ -79,7 +79,6 @@ cluster_t *flip_cluster(const graph_t *g, const double *ps, double H, bool *x, g
   // initiate the data structure for returning flip information
   c = (cluster_t *)calloc(1, sizeof(cluster_t));
   c->nv = 0;
-  c->dH = 0;
 
   n_h_bonds = 0; n_bonds = 0;
 
@@ -152,7 +151,7 @@ double *get_bond_probs(double T, double H, ising_state_t *s) {
   return ps;
 }
 
-int32_t wolff_step(double T, double H, ising_state_t *s, gsl_rng *r, double *ps) {
+uint32_t wolff_step(double T, double H, ising_state_t *s, gsl_rng *r, double *ps) {
   if (r == NULL) {
     r = gsl_rng_alloc(gsl_rng_mt19937);
     gsl_rng_set(r, jst_rand_seed());
@@ -167,8 +166,10 @@ int32_t wolff_step(double T, double H, ising_state_t *s, gsl_rng *r, double *ps)
   s->M += -2 * c->dM;
   s->H += 2 * c->dH;
 
+  uint32_t n_flips = c->nv;
+
   free(c);
 
-  return c->nv;
+  return n_flips;
 }