printer.cpp: In function 'void add(std::__cxx11::string)':
printer.cpp:9:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(i=0;i<s.size();i++){
~^~~~~~~~~
printer.cpp:11:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<aft[u].size();j++)
~^~~~~~~~~~~~~~
printer.cpp: In function 'void check(std::__cxx11::string)':
printer.cpp:25:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(i=0;i<s.size();i++){
~^~~~~~~~~
printer.cpp:27:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<aft[u].size();j++)
~^~~~~~~~~~~~~~
printer.cpp: In function 'void dfs(int)':
printer.cpp:37:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<V[u].size();i++){
~^~~~~~~~~~~~
printer.cpp:42:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<V[u].size();i++){
~^~~~~~~~~~~~
printer.cpp: In function 'int main()':
printer.cpp:52:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d" , &n);
~~~~~^~~~~~~~~~~
printer.cpp:54:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%s", s);
~~~~~^~~~~~~~~