foo.cc: In function ‘bool cmp(Node, Node)’:
foo.cc:11:33: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
   11 |         return x.s>y.s||x.s==y.s&&x.id<y.id;
      |                         ~~~~~~~~^~~~~~~~~~~
foo.cc: In function ‘int main()’:
foo.cc:19:30: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   19 |                 for(int i=0;i<s1.size();i++)
      |                             ~^~~~~~~~~~
foo.cc:25:24: warning: ‘x’ may be used uninitialized [-Wmaybe-uninitialized]
   25 |                 if(!v[x])cnt++;
      |                     ~~~^
foo.cc:18:28: note: ‘x’ was declared here
   18 |                 cin>>s;int x;
      |                            ^