Compilare: user.cpp:2:80: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] std::ifstream f("cufar.in");long long s,i=1,j=2,t,n,x,k,o[1<<20],z[1<<20];main(){f>>t>>n;for(;i<=n;++i)f>>x>>k,z[x]=k;for(j;j<=1e6;++j)if(!o[i])for(j=i;j<=1e6;j+=i)if(++o[j]==z[j])s+=i;std::ofstream("cufar.out")<<s;} ^ user.cpp: In function ‘int main()’: user.cpp:2:124: warning: statement has no effect [-Wunused-value] std::ifstream f("cufar.in");long long s,i=1,j=2,t,n,x,k,o[1<<20],z[1<<20];main(){f>>t>>n;for(;i<=n;++i)f>>x>>k,z[x]=k;for(j;j<=1e6;++j)if(!o[i])for(j=i;j<=1e6;j+=i)if(++o[j]==z[j])s+=i;std::ofstream("cufar.out")<<s;} ^