/in/foo.cc: In member function 'void sccTarjan::tarjan(int)':
/in/foo.cc:11:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define re(i,s,t) for(int i=s;i<t;++i)
                                 
/in/foo.cc:46:12:
         re(i,0,graph[x].size())
            ~~~~~~~~~~~~~~~~~~~  
/in/foo.cc:46:9: note: in expansion of macro 're'
         re(i,0,graph[x].size())
         ^~
/in/foo.cc:48:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(i==graph[x].size())break;
                ~^~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:11:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define re(i,s,t) for(int i=s;i<t;++i)
                                 
/in/foo.cc:110:16:
             re(j,0,tar.graph[i].size())
                ~~~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:110:13: note: in expansion of macro 're'
             re(j,0,tar.graph[i].size())
             ^~
/in/foo.cc:11:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define re(i,s,t) for(int i=s;i<t;++i)
                                 
/in/foo.cc:124:20:
                 re(j,0,newgraph[i].size())
                    ~~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:124:17: note: in expansion of macro 're'
                 re(j,0,newgraph[i].size())
                 ^~