Compilare: user.cpp: In function ‘void delete_spaces(char*)’: user.cpp:27:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i=0;i<strlen(c);i++) ^ user.cpp:29:11: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(c[i]=='\"' && contor%2==0) ^ user.cpp: In function ‘void extract_header(FILE*, FILE*)’: user.cpp:96:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(c,1025,f); ^ user.cpp: In function ‘void extract_columns(FILE*, FILE*)’: user.cpp:128:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(c,1025,f); ^