diff --git a/cmd/joj3/conf.go b/cmd/joj3/conf.go
index 0556478..038a4ac 100644
--- a/cmd/joj3/conf.go
+++ b/cmd/joj3/conf.go
@@ -3,7 +3,9 @@ package main
 import (
 	"fmt"
 	"log/slog"
+	"os"
 	"regexp"
+	"strconv"
 	"strings"
 
 	"focs.ji.sjtu.edu.cn/git/FOCS-dev/JOJ3/internal/stage"
@@ -11,6 +13,14 @@ import (
 	"github.com/koding/multiconfig"
 )
 
+type JobType int
+
+const (
+	HC JobType = iota
+	CQ
+	OJ
+)
+
 type Conf struct {
 	SandboxExecServer string `default:"localhost:5051"`
 	SandboxToken      string `default:""`
@@ -81,7 +91,7 @@ func parseConfFile(path string) (conf Conf, err error) {
 	return
 }
 
-func validateHw(hw string) error {
+func _validateHw(hw string) error {
 	matched, err := regexp.MatchString(`^hw[0-9]+$`, hw)
 	if err != nil {
 		return fmt.Errorf("error compiling regex: %w", err)
@@ -92,7 +102,36 @@ func validateHw(hw string) error {
 	return nil
 }
 
-func commitMsgToConf() (conf Conf, err error) {
+func _getExList(pattern string) (hwList []string, err error) {
+	re, err := regexp.Compile(pattern)
+	if err != nil {
+		return nil, fmt.Errorf("failed to compile regex: %w", err)
+	}
+
+	files, err := os.ReadDir(".")
+	if err != nil {
+		return nil, fmt.Errorf("error reading directory: %w", err)
+	}
+
+	for _, file := range files {
+		if !file.IsDir() && re.MatchString(file.Name()) {
+			hwList = append(hwList, file.Name())
+		}
+	}
+
+	return hwList, nil
+}
+
+func _contains(list []string, item string) bool {
+	for _, v := range list {
+		if v == item {
+			return true
+		}
+	}
+	return false
+}
+
+func commitMsgToConf() (confs []Conf, jobtype JobType, err error) {
 	r, err := git.PlainOpen(".")
 	if err != nil {
 		return
@@ -108,51 +147,75 @@ func commitMsgToConf() (conf Conf, err error) {
 		return
 	}
 
+	var conf Conf
+	var exList []string
+	jobtype = HC
 	file := "conf.json"
 
 	msg := commit.Message
 	slog.Debug("commit msg to conf", "msg", msg)
+
+	// INFO: default config
+	conf, err = parseConfFile(file)
+	confs = append(confs, conf)
 	if msg == "" {
-		conf, err = parseConfFile(file)
 		return
 	}
 
 	line := strings.Split(msg, "\n")[0]
-
 	words := strings.Fields(line)
-
 	head := words[0]
+
 	var hw string
 
+	// INFO: get worktype
 	if strings.HasSuffix(head, ":") || strings.HasSuffix(head, ".") {
 		head = head[:len(head)-1]
 	}
-
 	switch head {
 	case "feat", "fix", "refactor", "perf", "test", "build", "revert":
-		// TODO: Decide strategy to give students error
-		// if len(words) < 2 {
-		// 	return Conf{}, fmt.Errorf("error: hw not assigned")
-		// }
-		if len(words) >= 2 {
-			hw = words[1]
-			if err = validateHw(hw); err == nil {
-				file = strings.Replace(file, "conf", "conf-"+hw+"-cq", 1)
-			}
-		}
+		jobtype = CQ
 	case "joj", "grading":
-		// TODO: Decide strategy to give students error
-		// if len(words) < 2 {
-		// 	return Conf{}, fmt.Errorf("error: hw not assigned")
-		// }
-		if len(words) >= 2 {
-			hw = words[1]
-			if err = validateHw(hw); err == nil {
-				file = strings.Replace(file, "conf", "conf-"+hw+"-oj", 1)
+		jobtype = OJ
+	}
+
+	// INFO: get configs
+	if len(words) >= 2 {
+		hw = words[1]
+		if err = _validateHw(hw); err == nil {
+			file = strings.Replace(file, "conf", "conf-"+hw, 1)
+		}
+		var exTot []string
+
+		// INFO: get all hw ex if no args provided
+		exTot, err = _getExList(file)
+		if len(words) == 2 {
+			exList = exTot
+		} else {
+			var tmpList []string
+			for idx := 2; idx < len(words); idx++ {
+				word := words[idx]
+				num, err := strconv.Atoi(word)
+				if err != nil {
+					return confs, HC, fmt.Errorf("error: bad ex number")
+				}
+				file := fmt.Sprintf("conf-"+hw+"-ex%d.json", num)
+				if !_contains(exList, file) {
+					return confs, HC, fmt.Errorf("error: bad ex number")
+				}
+				tmpList = append(tmpList, file)
 			}
+			exList = tmpList
 		}
 	}
 
-	conf, err = parseConfFile(file)
+	for _, ex := range exList {
+		conf, err = parseConfFile(ex)
+		if err != nil {
+			return
+		}
+		confs = append(confs, conf)
+	}
+
 	return
 }
diff --git a/cmd/joj3/main.go b/cmd/joj3/main.go
index 8d9f91c..c4039ee 100644
--- a/cmd/joj3/main.go
+++ b/cmd/joj3/main.go
@@ -71,11 +71,12 @@ func outputResult(conf Conf, results []stage.StageResult) error {
 }
 
 func mainImpl() error {
-	conf, err := commitMsgToConf()
+	conf, jobtype, err := commitMsgToConf()
 	if err != nil {
 		slog.Error("no conf found", "error", err)
 		return err
 	}
+	// TODO: implementation for multiple configs
 	setupSlog(conf)
 	executors.InitWithConf(conf.SandboxExecServer, conf.SandboxToken)
 	stages, err := generateStages(conf)