Compilare: user.cpp: In function ‘void dfs2(int, int)’: user.cpp:43:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( x < bcc.size() ) { ^ user.cpp:52:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0, ok = 1; i < bcc[x].size(); i ++, ok = 1 ) { ^ user.cpp: In function ‘void dfs3(int, int, int)’: user.cpp:77:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( x < bcc.size() ) { ^ user.cpp:78:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < bcc[x].size(); i ++ ) { ^ user.cpp: In function ‘int main(int, const char**)’: user.cpp:116:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < bcc.size(); i ++ ) { ^ user.cpp:117:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int j = 0; j < bcc[i].size(); j ++ ) { ^ user.cpp:118:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int k = 0; k < bcc[i].size(); k ++ ) { ^ user.cpp: In function ‘void dfs3(int, int, int)’: user.cpp:96:34: warning: ‘aux’ may be used uninitialized in this function [-Wmaybe-uninitialized] dfs3( y, x, aux ); } } } ^