Compilare: main.cpp: In function 'void semn()': main.cpp:38:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(long long j = 0; j < primes.size() && val != 1; j++) ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void dfs(long long int, long long int)': main.cpp:57:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(long long it = 0; it < v[node].size(); it++) ~~~^~~~~~~~~~~~~~~~