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| public class NumberofIslands {
public int numIslands(char[][] grid) {
if (grid.length == 0) return 0;
int m = grid.length-1;
if (grid[0].length == 0) return 0;
int n = grid[0].length-1;
int count = 0;
for(int i=0; i<=m; i++) {
for (int j=0; j<=n; j++) {
if (grid[i][j] == '1') {
removeIsland(grid, i, j);
count ++;
}
}
}
return count;
}
public void removeIsland(char[][] grid, int i, int j) {
if (i<0 || j<0 || i>grid.length-1 || j>grid[0].length-1) return ;
if (grid[i][j] == '0') return;
grid[i][j] = '0';
removeIsland(grid, i-1,j);
removeIsland(grid, i+1, j);
removeIsland(grid, i, j-1);
removeIsland(grid, i, j+1);
}
}
|
