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Author: fwqaaq

problems/0200.岛屿数量.深搜版.md

@@ -413,13 +413,13 @@ func numIslands(grid [][]byte) int {
 }
 
 func dfs(grid [][]byte, visited [][]bool, i, j int) {
+        visited[x][y] = true
 	for _, d := range DIRECTIONS {
 		x, y := i+d[0], j+d[1]
 		if x < 0 || x >= len(grid) || y < 0 || y >= len(grid[0]) {
 			continue
 		}
 		if grid[x][y] == '1' && !visited[x][y] {
-			visited[x][y] = true
 			dfs(grid, visited, x, y)
 		}
 	}