Compilare: user.cpp: In function ‘int main()’: user.cpp:178:6: warning: unused variable ‘j’ [-Wunused-variable] int j = -1; ^ user.cpp:212:2: warning: label ‘done1’ defined but not used [-Wunused-label] done1:; ^~~~~ user.cpp: In function ‘int i32()’: user.cpp:141:23: 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,LEN,f); ^ user.cpp:149:23: 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,LEN,f); ^