Compilare: main.cpp:1:2: warning: #import is a deprecated GCC extension [-Wdeprecated] #import<bits/stdc++.h> ^~~~~~ main.cpp:2:120: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] std::ifstream f("reactivi.in");std::ofstream g("reactivi.out");std::pair<int,int>v[8003];int i,n,nr,cri((-1<<30));main(){f>>n;for(i=0;i<n;++i)f>>v[i].second>>v[i].first;std::sort(v,v+n);for(i=0;i<n;++i)if(cri<v[i].second)nr++,cri=v[i].first;g<<nr<<"\n";} ^