Compilare: user.cpp: In function ‘int bfs()’: user.cpp:20:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[x].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:63:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[2 * n + 1].size(); ++i) { ^ user.cpp:90:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < ans.size(); ++i) { ^ user.cpp:61:9: warning: unused variable ‘flow’ [-Wunused-variable] int flow = 0; ^ user.cpp:39:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &n); ^ user.cpp:42:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &in, &out); ^