refactor and to go mod

server/utils/prallel.go

@@ -0,0 +1,17 @@
+package utils
+
+import (
+	"sync"
+)
+
+func ParallelFor(begin, end int, fn func(i int)) {
+	var wg sync.WaitGroup
+	wg.Add(end - begin)
+	for i := begin; i < end; i++ {
+		go func(i int) {
+			fn(i)
+			wg.Done()
+		}(i)
+	}
+	wg.Wait()
+}