Compilare: user.cpp: In function ‘int main()’: user.cpp:249: warning: comparison between signed and unsigned integer expressions user.cpp:301: warning: comparison between signed and unsigned integer expressions user.cpp:313: warning: comparison between signed and unsigned integer expressions user.cpp:314: warning: comparison between signed and unsigned integer expressions user.cpp:320: warning: comparison between signed and unsigned integer expressions user.cpp:321: warning: comparison between signed and unsigned integer expressions user.cpp:333: warning: comparison between signed and unsigned integer expressions user.cpp:334: warning: comparison between signed and unsigned integer expressions user.cpp:353: warning: comparison between signed and unsigned integer expressions user.cpp:354: warning: comparison between signed and unsigned integer expressions user.cpp:364: warning: comparison between signed and unsigned integer expressions user.cpp:365: warning: comparison between signed and unsigned integer expressions user.cpp:370: warning: comparison between signed and unsigned integer expressions user.cpp:371: warning: comparison between signed and unsigned integer expressions user.cpp:380: warning: comparison between signed and unsigned integer expressions user.cpp:221: warning: unused variable ‘lastj’ user.cpp:224: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:226: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:228: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:383: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result