Compilare: user.cpp: In function ‘int main()’: user.cpp:91:13: warning: unused variable ‘j’ [-Wunused-variable] int n,i,j,op,m,nr; ^ user.cpp:91:20: warning: unused variable ‘nr’ [-Wunused-variable] int n,i,j,op,m,nr; ^ user.cpp: In function ‘void read(int&)’: user.cpp:75:36: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,DIM,stdin); ^ user.cpp:82:32: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,DIM,stdin); ^ user.cpp: In function ‘int main()’: user.cpp:89:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rest.in","r",stdin); ^ user.cpp:90:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rest.out","w",stdout); ^ user.cpp:92:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,DIM,stdin); ^