/in/foo.cc: In function 'void spfa(int)':
/in/foo.cc:52:17: error: no match for call to '(std::bitset<20>) (int&)'
   52 |             tmp1(chg);
      |             ~~~~^~~~~
/in/foo.cc:63:42: warning: comparison of integer expressions of different signedness: 'std::size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   63 |                         if (tmp1.count() <= m-1) {
      |                             ~~~~~~~~~~~~~^~~~~~
/in/foo.cc:51:42: warning: unused variable 'cnt' [-Wunused-variable]
   51 |                         int chg = t ^ i, cnt = 0, f = 1, temp = i;
      |                                          ^~~
/in/foo.cc:51:51: warning: unused variable 'f' [-Wunused-variable]
   51 |                         int chg = t ^ i, cnt = 0, f = 1, temp = i;
      |                                                   ^
/in/foo.cc:51:58: warning: unused variable 'temp' [-Wunused-variable]
   51 |                         int chg = t ^ i, cnt = 0, f = 1, temp = i;
      |                                                          ^~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:85:32: error: overloaded function with no contextual type information
   85 |         end = (1 << (n + 1)) - 1;
      |                                ^