Compilare: user.cpp: In function ‘void afla(int)’: user.cpp:64:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<g[nod].size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:75:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lant.in","r",stdin); ^ user.cpp:76:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lant.out","w",stdout); ^ user.cpp:78:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &k); ^ user.cpp:79:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp:89:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccoBGZHz.o: In function `main': user.cpp:(.text.startup+0x69): warning: the `gets' function is dangerous and should not be used.