railway.cpp: In function 'void dfs(int, int)':
railway.cpp:16:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
16 | for(int i=0;i<e[nw].size();i++){
| ~^~~~~~~~~~~~~
railway.cpp: In function 'void fdfs(int, int, int)':
railway.cpp:39:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
39 | for(int i=0;i<e[nw].size();i++){
| ~^~~~~~~~~~~~~
railway.cpp:52:19: warning: comparison of integer expressions of different signedness: 'std::set<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
52 | if(ptad[nw].size()>=K){
| ~~~~~~~~~~~~~~~^~~
railway.cpp: In function 'int main()':
railway.cpp:71:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
71 | for(int i=1;i<dfn.size();i++){
| ~^~~~~~~~~~~
railway.cpp:78:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
78 | for(int j=1;j+(1<<i)-1<=dfn.size()-1;j++){
| ~~~~~~~~~~^~~~~~~~~~~~~~
railway.cpp:97:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
97 | for(int i=1;i<vc.size();i++){
| ~^~~~~~~~~~
railway.cpp:88:9: warning: unused variable 'a' [-Wunused-variable]
88 | int a;int b;
| ^
railway.cpp:88:15: warning: unused variable 'b' [-Wunused-variable]
88 | int a;int b;
| ^
railway.cpp:105:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
105 | for(int i=0;i<ans.size();i++){
| ~^~~~~~~~~~~