Compilare: user.cpp: In function ‘double bellman_ford()’: user.cpp:64: warning: comparison between signed and unsigned integer expressions user.cpp:54: warning: unused variable ‘j’ user.cpp: In function ‘int pair_up(int)’: user.cpp:122: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:176: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:177: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:178: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:183: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:188: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result