diff --git a/README.md b/README.md
index 079377933c..9f27fc5088 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,7 @@ Your ideas/fixes/algorithms are more than welcome!
|-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
|1022|[Sum of Root To Leaf Binary Numbers](https://leetcode.com/problems/sum-of-root-to-leaf-binary-numbers/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1022.java) | O(n) | O(n) | |Easy|
|1021|[Remove Outermost Parentheses](https://leetcode.com/problems/remove-outermost-parentheses/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1021.java) | O(n) | O(n) | |Easy|
+|1020|[Number of Enclaves](https://leetcode.com/problems/number-of-enclaves/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1020.java) | O(mn) | O(mn) | |Medium|Graph, DFS, BFS, recursion|
|1018|[Binary Prefix Divisible By 5](https://leetcode.com/problems/binary-prefix-divisible-by-5/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1018.java) | O(n) | O(1) | |Easy|
|1013|[Pairs of Songs With Total Durations Divisible by 60](https://leetcode.com/problems/pairs-of-songs-with-total-durations-divisible-by-60/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1013.java) | O(n) | O(1) | |Easy|
|1009|[Complement of Base 10 Integer](https://leetcode.com/problems/complement-of-base-10-integer/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1009.java) | O(n) | O(1) | |Easy|
diff --git a/src/main/java/com/fishercoder/solutions/_1020.java b/src/main/java/com/fishercoder/solutions/_1020.java
new file mode 100644
index 0000000000..eec5f59fc8
--- /dev/null
+++ b/src/main/java/com/fishercoder/solutions/_1020.java
@@ -0,0 +1,53 @@
+package com.fishercoder.solutions;
+
+/**
+ * Given a 2D array A, each cell is 0 (representing sea) or 1 (representing land)
+ *
+ * A move consists of walking from one land square 4-directionally to another land square, or off the boundary of the grid.
+ *
+ * Return the number of land squares in the grid for which we cannot walk off the boundary of the grid in any number of moves.
+ */
+
+public class _1020 {
+ public static class Solution1 {
+ public void walk(int[][] A, boolean[][] visited, int x, int y) {
+ if (x >= A.length || x < 0 || y >= A[0].length || y < 0) return;
+ if (visited[x][y]) return;
+ if (A[x][y] == 0) return;
+
+ visited[x][y] = true;
+
+ walk(A, visited, x - 1, y);
+ walk(A, visited, x, y - 1);
+ walk(A, visited, x, y + 1);
+ walk(A, visited, x + 1, y);
+ }
+
+ public int numEnclaves(int[][] A) {
+ int n = A.length;
+ int m = A[0].length;
+ boolean[][] visited = new boolean[n][m];
+
+ for (int i = 0; i < n; ++i) {
+ walk(A, visited, i, 0);
+ walk(A, visited, i, m - 1);
+ }
+
+ for (int j = 0; j < m; ++j) {
+ walk(A, visited, 0, j);
+ walk(A, visited, n - 1, j);
+ }
+
+ int unreachables = 0;
+ for (int i = 0; i < n; ++i) {
+ for (int j = 0; j < m; ++j) {
+ if (A[i][j] == 1 && !visited[i][j]) {
+ ++unreachables;
+ }
+ }
+ }
+
+ return unreachables;
+ }
+ }
+}
diff --git a/src/test/java/com/fishercoder/_1020Test.java b/src/test/java/com/fishercoder/_1020Test.java
new file mode 100644
index 0000000000..359557c6c3
--- /dev/null
+++ b/src/test/java/com/fishercoder/_1020Test.java
@@ -0,0 +1,54 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1020;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1020Test {
+ private static _1020.Solution1 solution1;
+
+ @BeforeClass
+ public static void setup() {
+ solution1 = new _1020.Solution1();
+ }
+
+ @Test
+ public void test1() {
+ int[][] map = {
+ {0, 0, 0, 0},
+ {1, 0, 1, 0},
+ {0, 1, 1, 0},
+ {0, 0, 0, 0}
+ };
+
+ assertEquals(solution1.numEnclaves(map), 3);
+ }
+
+ @Test
+ public void test2() {
+ int[][] map = {
+ {0, 1, 1, 0},
+ {0, 0, 1, 0},
+ {0, 0, 1, 0},
+ {0, 0, 0, 0}
+ };
+
+ assertEquals(solution1.numEnclaves(map), 0);
+ }
+
+ @Test
+ public void test3() {
+ int[][] map = {
+ {0, 1, 1, 0},
+ {0, 0, 0, 0},
+ {1, 0, 1, 0},
+ {1, 0, 0, 0},
+ {0, 1, 1, 0},
+ {0, 0, 0, 0},
+ };
+
+ assertEquals(solution1.numEnclaves(map), 3);
+ }
+}
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