refactor: reorganize progress line formatting

Author: wbruna

util.cpp

@@ -269,13 +269,16 @@ void pretty_progress(int step, int steps, float time) {
         }
     }
     progress += "|";
-    printf(time > 1.0f ? "\r%s %i/%i - %.2fs/it\033[K" : "\r%s %i/%i - %.2fit/s\033[K",
-           progress.c_str(), step, steps,
-           time > 1.0f || time == 0 ? time : (1.0f / time));
-    fflush(stdout);  // for linux
-    if (step == steps) {
-        printf("\n");
+
+    const char* lf   = (step == steps ? "\n" : "");
+    const char* unit = "s/it";
+    float speed      = time;
+    if (speed < 1.0f && speed > 0.f) {
+        speed = 1.0f / speed;
+        unit  = "it/s";
     }
+    printf("\r%s %i/%i - %.2f%s\033[K%s", progress.c_str(), step, steps, speed, unit, lf);
+    fflush(stdout);  // for linux
 }
 
 std::string ltrim(const std::string& s) {