View Compilation Error

0_0_28013323_26031.cpp: In function 'double dfs(int, int)':
0_0_28013323_26031.cpp:20:9: error: expected unqualified-id before 'not' token
     int not = limit & ~x;
         ^
0_0_28013323_26031.cpp:21:14: error: expected primary-expression before ')' token
     while(not)
              ^
0_0_28013323_26031.cpp:23:28: error: expected primary-expression before ')' token
         int w = not & (-not);
                            ^
0_0_28013323_26031.cpp:25:13: error: expected primary-expression before '-=' token
         not -= w;
             ^