diff --git a/20201208/main.go b/20201208/main.go
new file mode 100644
index 0000000..d83af75
--- /dev/null
+++ b/20201208/main.go
@@ -0,0 +1,31 @@
+package main
+
+import "fmt"
+
+func main() {
+}
+
+func canSeparate(src []int) bool {
+	//A[0] + A[1] + ... + A[i] == A[i+1] + A[i+2] + ... + A[j-1] == A[j] + A[j-1] + ... + A[A.length - 1]
+	l := len(src)
+	for i := 1; i < l-1; i++ {
+		for j := i + 1; j < l; j++ {
+			s1 := sumSlice(src[:i])
+			s2 := sumSlice(src[i:j])
+			s3 := sumSlice(src[j:])
+			if s1 == s2 && s2 == s3 {
+				fmt.Println("separated on: ", i, j)
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func sumSlice(src []int) int {
+	ret := 0
+	for _, n := range src {
+		ret += n
+	}
+	return ret
+}
diff --git a/20201208/main_test.go b/20201208/main_test.go
new file mode 100644
index 0000000..b7f19ae
--- /dev/null
+++ b/20201208/main_test.go
@@ -0,0 +1,90 @@
+package main
+
+import "testing"
+
+func Test_canSeparate(t *testing.T) {
+	type args struct {
+		src []int
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			"test1",
+			args{
+				[]int{1, 1, 1},
+			},
+			true,
+		},
+		{
+			"test1",
+			args{
+				[]int{0, 2, 1, -6, 6, -7, 9, 1, 2, 0, 1},
+			},
+			true,
+		},
+		{
+			"test2",
+			args{
+				[]int{0, 2, 1, -6, 6, 7, 9, -1, 2, 0, 1},
+			},
+			false,
+		},
+		{
+			"test3",
+			args{
+				[]int{3, 3, 6, 5, -2, 2, 5, 1, -9, 4},
+			},
+			true,
+		},
+		{
+			"test4",
+			args{
+				[]int{10, -10, 10, -10, 10, -10, 10, -10},
+			},
+			false,
+		},
+		{
+			"test5",
+			args{
+				[]int{1, -1, 1, -1},
+			},
+			false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := canSeparate(tt.args.src); got != tt.want {
+				t.Errorf("canSeparate() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_sumSlice(t *testing.T) {
+	type args struct {
+		src []int
+	}
+	tests := []struct {
+		name string
+		args args
+		want int
+	}{
+		{
+			"test1",
+			args{
+				[]int{1, 2},
+			},
+			3,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := sumSlice(tt.args.src); got != tt.want {
+				t.Errorf("sumSlice() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}