Compilare: user.cpp: In function ‘void Solver()’: user.cpp:6:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= sum ; ++i) ^ user.cpp: In function ‘void back(int)’: user.cpp:11:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(k == n + 1){ ^ user.cpp:16:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = x; i <= sum ; ++i) ^ user.cpp: In function ‘int main()’: user.cpp:28:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= n ; ++i) ^ user.cpp:25:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("monezi.in", "r", stdin); ^ user.cpp:26:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("monezi.out", "w", stdout); ^ user.cpp:27:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &sum); ^ user.cpp:29:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^