规范格式

leetcode/1020.Number-of-Enclaves/1020. Number of Enclaves.go

@@ -0,0 +1,46 @@
+package leetcode
+
+var dir = [][]int{
+	[]int{-1, 0},
+	[]int{0, 1},
+	[]int{1, 0},
+	[]int{0, -1},
+}
+
+func numEnclaves(A [][]int) int {
+	m, n := len(A), len(A[0])
+	for i := 0; i < m; i++ {
+		for j := 0; j < n; j++ {
+			if i == 0 || i == m-1 || j == 0 || j == n-1 {
+				if A[i][j] == 1 {
+					dfsNumEnclaves(A, i, j)
+				}
+			}
+		}
+	}
+	count := 0
+	for i := 0; i < m; i++ {
+		for j := 0; j < n; j++ {
+			if A[i][j] == 1 {
+				count++
+			}
+		}
+	}
+	return count
+}
+
+func dfsNumEnclaves(A [][]int, x, y int) {
+	if !isInGrid(A, x, y) || A[x][y] == 0 {
+		return
+	}
+	A[x][y] = 0
+	for i := 0; i < 4; i++ {
+		nx := x + dir[i][0]
+		ny := y + dir[i][1]
+		dfsNumEnclaves(A, nx, ny)
+	}
+}
+
+func isInGrid(grid [][]int, x, y int) bool {
+	return x >= 0 && x < len(grid) && y >= 0 && y < len(grid[0])
+}