diff --git a/hw05_parallel_execution/run.go b/hw05_parallel_execution/run.go
index 54bfeef..da2eb65 100644
--- a/hw05_parallel_execution/run.go
+++ b/hw05_parallel_execution/run.go
@@ -9,25 +9,31 @@ import (
 var ErrErrorsLimitExceeded = errors.New("errors limit exceeded")
 
 type Task func() error
+type Errors struct {
+	count int
+	mx    sync.Mutex
+}
 
-// Run starts tasks in N goroutines and stops its work when receiving M errors from tasks
-func Run(tasks []Task, N int, M int) error {
-	log.Println("Tasks:", len(tasks), "| Goroutines:", N, "| Errors:", M)
-	errs := 0
-	for i := 0; i < len(tasks); i = i + N {
+func Run(tasks []Task, n int, m int) error {
+	log.Println("Tasks:", len(tasks), "| Goroutines:", n, "| Errors:", m)
+	errs := Errors{}
+	for i := 0; i < len(tasks); i += n {
 		wg := sync.WaitGroup{}
-		for g := 1; g <= N && i+g < len(tasks); g++ {
+		for g := 1; g <= n && i+g < len(tasks); g++ {
 			wg.Add(1)
-			go func(rt Task, i int, g int, errs *int) {
-				if err := rt; err != nil {
-					*errs++
+			go func(rt Task, errs *Errors) {
+				err := rt
+				if err != nil {
+					errs.mx.Lock()
+					errs.count++
+					errs.mx.Unlock()
 				}
 				wg.Done()
-			}(tasks[i+g], i, g, &errs)
+			}(tasks[i+g], &errs)
 		}
 		wg.Wait()
-		if errs > M {
-			log.Println("Produced", errs, "errors of", M)
+		if errs.count > m {
+			log.Println("Produced", errs.count, "errors of", m)
 			return ErrErrorsLimitExceeded
 		}
 	}