soltion of fibonacci_number problem and tests

Author: emikhalev

leetcode/fibonacci_number/fibonacci_number.go

@@ -0,0 +1,9 @@
+// https://leetcode.com/problems/fibonacci-number/
+package fibonacci_number
+
+func fib(n int) int {
+	if n == 0 || n == 1 {
+		return n
+	}
+	return fib(n-1) + fib(n-2)
+}

leetcode/fibonacci_number/fibonacci_number_test.go

@@ -0,0 +1,26 @@
+package fibonacci_number
+
+import (
+	"testing"
+)
+
+func Test_fib(t *testing.T) {
+	cases := []struct {
+		num      int
+		expected int
+	}{
+		{0, 0},
+		{1, 1},
+		{2, 1},
+		{3, 2},
+		{4, 3},
+		{30, 832040},
+	}
+
+	for idx, tc := range cases {
+		res := fib(tc.num)
+		if tc.expected != res {
+			t.Errorf("case %d. expecting %d, got %d", idx, tc.expected, res)
+		}
+	}
+}