feat: friday

pkg/pacific_atlantic_water_flow/main_test.go

@@ -0,0 +1,62 @@
+package pacificatlanticwaterflow
+
+import (
+	"sort"
+	"testing"
+)
+
+func sortResult(result [][]int) {
+	sort.Slice(result, func(i, j int) bool {
+		if result[i][0] != result[j][0] {
+			return result[i][0] < result[j][0]
+		}
+		return result[i][1] < result[j][1]
+	})
+}
+
+func TestPacificAtlantic(t *testing.T) {
+	tests := []struct {
+		name     string
+		heights  [][]int
+		expected [][]int
+	}{
+		{
+			name: "5x5 grid",
+			heights: [][]int{
+				{1, 2, 2, 3, 5},
+				{3, 2, 3, 4, 4},
+				{2, 4, 5, 3, 1},
+				{6, 7, 1, 4, 5},
+				{5, 1, 1, 2, 4},
+			},
+			expected: [][]int{{0, 4}, {1, 3}, {1, 4}, {2, 2}, {3, 0}, {3, 1}, {4, 0}},
+		},
+		{
+			name: "3x2 all ones",
+			heights: [][]int{
+				{1, 1},
+				{1, 1},
+				{1, 1},
+			},
+			expected: [][]int{{0, 0}, {0, 1}, {1, 0}, {1, 1}, {2, 0}, {2, 1}},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			result := PacificAtlantic(tc.heights)
+			sortResult(result)
+			sortResult(tc.expected)
+
+			if len(result) != len(tc.expected) {
+				t.Fatalf("expected %d results, got %d: %v", len(tc.expected), len(result), result)
+			}
+
+			for i := range tc.expected {
+				if result[i][0] != tc.expected[i][0] || result[i][1] != tc.expected[i][1] {
+					t.Errorf("result[%d] = %v, expected %v", i, result[i], tc.expected[i])
+				}
+			}
+		})
+	}
+}