Compilare: user.cpp: In function ‘int main()’: user.cpp:31:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<sol.size();++i) printf("%d %d %d\n",sol[i].first,sol[i].second.first,sol[i].second.second); ^ user.cpp:12:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("minim.in","r",stdin); ^ user.cpp:13:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("minim.out","w",stdout); ^ user.cpp:14:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:15:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1;i<=n;++i) scanf("%d",&V[i]); ^