Compilare: user.cpp: In function ‘bool check(line)’: user.cpp:105: warning: comparison between signed and unsigned integer expressions user.cpp:128: warning: comparison between signed and unsigned integer expressions user.cpp:133: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:172: warning: comparison between signed and unsigned integer expressions user.cpp:174: warning: comparison between signed and unsigned integer expressions user.cpp:189: warning: comparison between signed and unsigned integer expressions user.cpp:216: warning: comparison between signed and unsigned integer expressions user.cpp:229: warning: comparison between signed and unsigned integer expressions user.cpp:243: warning: comparison between signed and unsigned integer expressions user.cpp:166: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:168: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result