Compilare: user.cpp: In function ‘int main()’: user.cpp:7:21: warning: unused variable ‘x’ [-Wunused-variable] long long N, i, j, x, max, index, optimum; ^ user.cpp:4:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.in","r",stdin); ^ user.cpp:5:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.out","w",stdout); ^ user.cpp:10:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld ", &N); ^ user.cpp:13:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld ", &a[i]); ^ user.cpp:38:24: warning: ‘index’ may be used uninitialized in this function [-Wmaybe-uninitialized] index = before[index]; ^