Compilare: main.cpp: In function 'void semn()': main.cpp:38:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < primes.size() && val > primes[j]; j++) ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void dfs(int, int)': main.cpp:57:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int it = 0; it < v[node].size(); it++) ~~~^~~~~~~~~~~~~~~~