diff --git a/20210121/main.go b/20210121/main.go
new file mode 100644
index 0000000..c05a524
--- /dev/null
+++ b/20210121/main.go
@@ -0,0 +1,31 @@
+package main
+
+import "strings"
+
+const balloon = "balloon"
+
+func main() {
+
+}
+
+func maxNumberOfBalloons(text string) int {
+	nt := text
+	lt := text
+	end := false
+	count := 0
+	for {
+		for _, c := range balloon {
+			nt = strings.Replace(lt, string(c), "", 1)
+			if nt == lt {
+				end = true
+				break
+			}
+			lt = nt
+		}
+		if end {
+			break
+		}
+		count++
+	}
+	return count
+}
diff --git a/20210121/main_test.go b/20210121/main_test.go
new file mode 100644
index 0000000..14dcedb
--- /dev/null
+++ b/20210121/main_test.go
@@ -0,0 +1,43 @@
+package main
+
+import "testing"
+
+func Test_maxNumberOfBalloons(t *testing.T) {
+	type args struct {
+		text string
+	}
+	tests := []struct {
+		name string
+		args args
+		want int
+	}{
+		{
+			"test1",
+			args{
+				"nlaebolko",
+			},
+			1,
+		},
+		{
+			"test2",
+			args{
+				"loonbalxballpoon",
+			},
+			2,
+		},
+		{
+			"test3",
+			args{
+				"leetcode",
+			},
+			0,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := maxNumberOfBalloons(tt.args.text); got != tt.want {
+				t.Errorf("maxNumberOfBalloons() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}