Compilare: main.cpp: In function 'int main()': main.cpp:137:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 137 | for(int i=1; i<ans.size(); i++) | ~^~~~~~~~~~~ main.cpp:173:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 173 | for(int i=0;i<rez.size();i++) | ~^~~~~~~~~~~ main.cpp:19:9: warning: variable 'last2a' set but not used [-Wunused-but-set-variable] 19 | int last2a,last2b; | ^~~~~~ main.cpp:19:16: warning: variable 'last2b' set but not used [-Wunused-but-set-variable] 19 | int last2a,last2b; | ^~~~~~ main.cpp:97:24: warning: 'lastb' may be used uninitialized in this function [-Wmaybe-uninitialized] 97 | if(lasta==x&&lastb!=y) | ~~~~~~~~^~~~~~~~~~ main.cpp:97:13: warning: 'lasta' may be used uninitialized in this function [-Wmaybe-uninitialized] 97 | if(lasta==x&&lastb!=y) | ^~