Merge pull request #44 from surechen/edit_format_for_expr_var

修复 'G.EXP.02  不宜在比较中使用不兼容的位掩码' 表格展示问题

Author: ZhangHanDong

src/safe-guides/coding_practice/expr.md

@@ -51,9 +51,9 @@ a += b;
 |== or != |	& | x & 2 == 3 | false | c & m != c|
 |< or >= |	& | x & 2 < 3 | true | m < c|
 |> or <= |	& | x & 1 > 1 | false | m <= c|
-|== or != |	| | x | 1 == 0 | false | c | m != c|
-|< or >= |	| | x | 1 < 1 | false | m >= c|
-|<= or > |	| | x | 1 > 0 | true | m > c|
+|== or != |	&#124; | x &#124; 1 == 0 | false | c &#124; m != c|
+|< or >= |	&#124; | x &#124; 1 < 1 | false | m >= c|
+|<= or > |	&#124; | x &#124; 1 > 0 | true | m > c|
 
 **【反例】**