Compilare: user.cpp: In function ‘bool check(line)’: user.cpp:108: warning: comparison between signed and unsigned integer expressions user.cpp:131: warning: comparison between signed and unsigned integer expressions user.cpp:136: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:179: warning: comparison between signed and unsigned integer expressions user.cpp:206: warning: comparison between signed and unsigned integer expressions user.cpp:219: warning: comparison between signed and unsigned integer expressions user.cpp:233: warning: comparison between signed and unsigned integer expressions user.cpp:169: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:171: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result