Compilare: user.cpp: In function ‘int bfs()’: user.cpp:50:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<a[nd].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:99:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<a[p].size();i++) ^ user.cpp:121:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0,ok=0;j<a[i].size();j++) ^ user.cpp:133:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<a[i].size();j++) ^ user.cpp:76:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&m); ^ user.cpp:77:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(st,2900,f); ^ user.cpp:81:31: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(st,2900,f); ^