Compilare: user.cpp: In function ‘bool check(line)’: user.cpp:121: warning: comparison between signed and unsigned integer expressions user.cpp:144: warning: comparison between signed and unsigned integer expressions user.cpp:149: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:167: warning: comparison between signed and unsigned integer expressions user.cpp:169: warning: comparison between signed and unsigned integer expressions user.cpp:184: warning: comparison between signed and unsigned integer expressions user.cpp:235: warning: comparison between signed and unsigned integer expressions user.cpp:161: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:163: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result