Compilare: user.cpp: In function ‘bool check1(std::vector<sp>, int)’: user.cpp:20:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();i++) ^ user.cpp:27:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();i++) ^ user.cpp: In function ‘bool check2(std::vector<sp>, int)’: user.cpp:38:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();i++) ^ user.cpp:47:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); i++) ^ user.cpp:57:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); i++) ^ user.cpp:66:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); i++) ^ user.cpp:75:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); i++) ^ user.cpp:37:30: warning: ‘y2’ may be used uninitialized in this function [-Wmaybe-uninitialized] int x1=50000,y1=50000,x2,y2; ^ user.cpp:37:27: warning: ‘x2’ may be used uninitialized in this function [-Wmaybe-uninitialized] int x1=50000,y1=50000,x2,y2; ^