Compilare: user.cpp: In function ‘int main()’: user.cpp:13:19: warning: unused variable ‘idx’ [-Wunused-variable] int i,p_i,p_f,idx; ^ user.cpp:10:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssm.in", "r", stdin); ^ user.cpp:11:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssm.out", "w", stdout); ^ user.cpp:15:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^ user.cpp:16:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1; i<=N; i++) scanf("%d",&a[i]); ^ user.cpp:30:15: warning: ‘p_f’ may be used uninitialized in this function [-Wmaybe-uninitialized] s+=a[i]; ^