Compilare: user.cpp: In function ‘bool check(line)’: user.cpp:128: warning: comparison between signed and unsigned integer expressions user.cpp:151: warning: comparison between signed and unsigned integer expressions user.cpp:156: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:178: warning: comparison between signed and unsigned integer expressions user.cpp:208: warning: comparison between signed and unsigned integer expressions user.cpp:168: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:170: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result