diff --git a/examples/bench.cc b/examples/bench.cc
index 0d857c2..20d02a8 100644
--- a/examples/bench.cc
+++ b/examples/bench.cc
@@ -155,7 +155,7 @@ char * new_string_from_integer(uint64_t num)
 {
     int ndigits = num == 0 ? 1 : (int)log10(num) + 1;
     char * str = (char *)malloc(ndigits + 1);
-    sprintf(str, "%zu", num);
+    sprintf(str, "%u", (unsigned int)num);
     return str;
 }
 
@@ -193,7 +193,8 @@ Timer _fill_random(vector<T> &v, HT &hash)
 // --------------------------------------------------------------------------
 void out(const char* test, int64_t cnt, const Timer &t, bool final = false)
 {
-    printf("%s,time,%zu,%s,%f\n", test, cnt, program_slug, (float)((double)t.elapsed().count() / 1000));
+    printf("%s,time,%u,%s,%f\n", test, (unsigned int)cnt, program_slug, 
+           (float)((double)t.elapsed().count() / 1000));
 }
 
 // --------------------------------------------------------------------------
@@ -202,7 +203,8 @@ void outmem(const char* test, int64_t cnt, uint64_t mem, bool final = false)
     static uint64_t max_mem = 0;
     static uint64_t max_keys = 0;
     if (final)
-        printf("peak memory usage for %zu values: %.2f GB\n",  max_keys, max_mem / ((double)1000 * 1000 * 1000));
+        printf("peak memory usage for %u values: %.2f GB\n",  (unsigned int)max_keys, 
+               max_mem / ((double)1000 * 1000 * 1000));
     else {
         if (mem > max_mem)
             max_mem = mem;
@@ -430,7 +432,7 @@ int main(int argc, char ** argv)
             size_t num_present;
 
             timer = _lookup(v, hash, num_present);
-            //fprintf(stderr, "found %llu\n", num_present);
+            //fprintf(stderr, "found %zu\n", num_present);
         }
         else if(!strcmp(argv[2], "delete"))
         {