Compilare: main.cpp: In function 'bool okcpp(ull)': main.cpp:22:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; sum < k; ++i) ~~~~^~~ main.cpp:24:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return (sum >= k && i >= p); ~~~~^~~~ main.cpp:24:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return (sum >= k && i >= p); ~~^~~~ main.cpp: In function 'void bkt(ull, ull, ull, int)': main.cpp:33:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(where == nr + 1) ~~~~~~^~~~~~~~~ main.cpp: In function 'bool work(int, bool)': main.cpp:57:17: warning: unused variable 'wh' [-Wunused-variable] int wh, st; ^~ main.cpp:57:21: warning: unused variable 'st' [-Wunused-variable] int wh, st; ^~