51:N 皇后

src/main/java/leetcode/editor/cn/NQueens.java

@@ -47,6 +47,7 @@ public class NQueens {
     public static void main(String[] args) {
         //测试代码
         Solution solution = new NQueens().new Solution();
+        solution.solveNQueens(4);
     }
 
     //力扣代码
@@ -80,10 +81,11 @@ public class NQueens {
                 }
 
                 String temp = list.get(row);
-                String s1 = temp;
                 temp = temp.substring(0, col) + "Q" + temp.substring(col + 1);
+                list.set(row,temp);
                 bfs(list, n, row + 1);
-
+                temp = temp.substring(0, col) + "." + temp.substring(col + 1);
+                list.set(row,temp);
             }
         }