Merge pull request #396 from openset/develop

Add: Factorial Trailing Zeroes

Author: Shuo

Diff for: problems/factorial-trailing-zeroes/factorial_trailing_zeroes.go

@@ -1 +1,8 @@
 package factorial_trailing_zeroes
+
+func trailingZeroes(n int) int {
+	if n < 5 {
+		return 0
+	}
+	return n/5 + trailingZeroes(n/5)
+}

Diff for: problems/factorial-trailing-zeroes/factorial_trailing_zeroes_test.go

@@ -1 +1,47 @@
 package factorial_trailing_zeroes
+
+import "testing"
+
+type caseType struct {
+	input    int
+	expected int
+}
+
+func TestTrailingZeroes(t *testing.T) {
+	tests := [...]caseType{
+		{
+			input:    3,
+			expected: 0,
+		},
+		{
+			input:    5,
+			expected: 1,
+		},
+		{
+			input:    7,
+			expected: 1,
+		},
+		{
+			input:    8,
+			expected: 1,
+		},
+		{
+			input:    10,
+			expected: 2,
+		},
+		{
+			input:    12,
+			expected: 2,
+		},
+		{
+			input:    25,
+			expected: 6,
+		},
+	}
+	for _, tc := range tests {
+		output := trailingZeroes(tc.input)
+		if output != tc.expected {
+			t.Fatalf("input: %v, output: %v, expected: %v", tc.input, output, tc.expected)
+		}
+	}
+}