Compilare: user.cpp: In function ‘bool check(line)’: user.cpp:107: warning: comparison between signed and unsigned integer expressions user.cpp:130: warning: comparison between signed and unsigned integer expressions user.cpp:135: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:174: warning: comparison between signed and unsigned integer expressions user.cpp:176: warning: comparison between signed and unsigned integer expressions user.cpp:192: warning: comparison between signed and unsigned integer expressions user.cpp:221: warning: comparison between signed and unsigned integer expressions user.cpp:234: warning: comparison between signed and unsigned integer expressions user.cpp:248: 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