Create 200-Number-of-Islands.java

Arrrsh · Jul 6, 2022 · 21f3182 · 21f3182
1 parent f67e6b0
commit 21f3182
Showing 1 changed file with 25 additions and 0 deletions.
diff --git a/java/200-Number-of-Islands.java b/java/200-Number-of-Islands.java
@@ -0,0 +1,25 @@
+class Solution {
+ public int numIslands(char[][] grid) {
+ int count = 0;
+ for (int i = 0; i<grid.length; i++) {
+ for (int j = 0; j<grid[0].length; j++) {
+ if (grid[i][j]=='1') {
+ dfs(grid, i, j);
+ count++;
+ }
+ }
+ }
+ return count;
+ }
+
+ public void dfs(char[][] grid, int i, int j) {
+ if (i<0 || j<0 || i>= grid.length || j>=grid[0].length || grid[i][j]=='0') {
+ return;
+ } 
+ grid[i][j] = '0';
+ dfs(grid, i+1, j);
+ dfs(grid, i, j+1);
+ dfs(grid, i-1, j);
+ dfs(grid, i, j-1);
+ }
+}