Compilare: user.cpp: In function ‘int main()’: user.cpp:60:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<cycle.size();i++) ^ user.cpp: In function ‘void build_cylces(std::vector<int>&)’: user.cpp:20:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i][0]); ^ user.cpp:25:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i][1]); ^ user.cpp: In function ‘int main()’: user.cpp:49:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("echival1.in", "r", stdin); ^ user.cpp:50:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("echival1.out", "w", stdout); ^ user.cpp:51:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^