Compilare: user.cpp: In function ‘void solve()’: user.cpp:124: warning: comparison between signed and unsigned integer expressions user.cpp:115: warning: unused variable ‘j’ user.cpp:115: warning: unused variable ‘k’ user.cpp: In function ‘int main()’: user.cpp:132: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:133: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:137: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:140: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result