Compilare: user.cpp: In function ‘long long unsigned int solve2(long long unsigned int)’: user.cpp:40:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < bigger.size(); ++i) { ^ user.cpp:24:9: warning: unused variable ‘nr’ [-Wunused-variable] int nr = 0; ^ user.cpp: In function ‘int main(int, const char**)’: user.cpp:52:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &V); ^ user.cpp:53:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%llu", &N); ^