Compilare: user.cpp: In function ‘int bfs()’: user.cpp:35:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (r=0;r<v[i].size();r++) { ^ user.cpp: In function ‘int main()’: user.cpp:88:23: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘long long int’ [-Wformat=] printf("%d\n",cost); ^ user.cpp:69:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,ok=1; ^ user.cpp:69:13: warning: unused variable ‘ok’ [-Wunused-variable] int i,j,ok=1; ^ user.cpp:67:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in","r",stdin); ^ user.cpp:68:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out","w",stdout); ^ user.cpp:71:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d",&n,&m,&source,&dest); ^ user.cpp:74:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d",&x,&y,&z,&k); ^