Compilare: main.cpp: In function 'int find_arb(int)': main.cpp:26:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int comb(int, int)': main.cpp:30:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned long long i=k+1; i<=n; i++) {c*=i; c%=mod; } ~^~~ main.cpp:31:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned long long i=1; i<=n-k; i++) {c/=i; c%=mod; } ~^~~~~