Compilare: user.cpp: In function ‘int main()’: user.cpp:31:22: warning: unused variable ‘pro’ [-Wunused-variable] long long lc,pro; ^ user.cpp:18:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suman.in", "r", stdin); ^ user.cpp:19:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suman.out", "w", stdout); ^ user.cpp:21:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &k); ^ user.cpp:23:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ user.cpp:46:33: warning: ‘lc’ may be used uninitialized in this function [-Wmaybe-uninitialized] sum += lc * (n/lc*(n/lc+1)/2); ^