fix: GCDSlice returns 1 when slice is empty

Signed-off-by: lowzj <[email protected]>
dragonflyoss · Apr 26, 2020 · 41a8604 · 41a8604
1 parent 06d2368
commit 41a8604
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diff --git a/pkg/algorithm/algorithm.go b/pkg/algorithm/algorithm.go
@@ -17,8 +17,13 @@
 package algorithm
 
 // GCDSlice returns the greatest common divisor of a slice.
+// It returns 1 when s is empty because that any number divided by 1 is still
+// itself.
 func GCDSlice(s []int) int {
 	length := len(s)
+	if length == 0 {
+		return 1
+	}
 	if length == 1 {
 		return s[0]
 	}

diff --git a/pkg/algorithm/algorithm_test.go b/pkg/algorithm/algorithm_test.go
@@ -53,6 +53,8 @@ func (suit *AlgorithmSuite) TestGCDSlice() {
 		slice  []int
 		result int
 	}{
+		{nil, 1},
+		{[]int{2}, 2},
 		{[]int{2, 2, 4}, 2},
 		{[]int{5, 10, 25}, 5},
 		{[]int{1, 3, 5}, 1},