feat: solve day 3 part 1

cmd/03/bank/bank_test.go

@@ -0,0 +1,53 @@
+package bank_test
+
+import (
+	"slices"
+	"testing"
+
+	"github.com/StevanFreeborn/advent-of-code-2025/cmd/03/bank"
+)
+
+func TestFrom(t *testing.T) {
+	expected := []int{1, 2, 3, 4, 5}
+	input := "12345"
+
+	result := bank.From(input)
+
+	if slices.Equal(result.Cells(), expected) == false {
+		t.Errorf("got %v but wanted %v", result.Cells(), expected)
+	}
+}
+
+type testCase struct {
+	bank     bank.Bank
+	expected int
+}
+
+func TestJoltage(t *testing.T) {
+	testCases := []testCase{
+		{
+			bank:     bank.From("987654321111111"),
+			expected: 98,
+		},
+		{
+			bank:     bank.From("811111111111119"),
+			expected: 89,
+		},
+		{
+			bank:     bank.From("234234234234278"),
+			expected: 78,
+		},
+		{
+			bank:     bank.From("818181911112111"),
+			expected: 92,
+		},
+	}
+
+	for _, testCase := range testCases {
+		result := testCase.bank.Joltage()
+
+		if result != testCase.expected {
+			t.Errorf("got %d but wanted %d", result, testCase.expected)
+		}
+	}
+}