Compilare: main.cpp:3:241: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] 3 | using namespace std;int N=1<<16,t,n,i,o,r;void j(auto&a,int q=0){auto b=a;y(r=n=a.size();r/=2;swap(a,b))y(i=0;i<n/2;i+=r)y(o=0;o<r;){auto u=a[i*2+o],v=polar(1.,2*M_PI/n*(q?-i:i))*a[i*2+o+r];b[i+o]=u+v;b[i+n/2+o++]=u-v;}y(auto&x:a)x/=q?n:1;}main(){fstream g("bacterii2.in"),l("bacterii2.out",ios::out);y(g>>t;t--;){vector p(N,0i),q=p;y(g>>n;n--;p[r]+=1)g>>r;y(g>>o;o--;q[r]+=1)g>>r;j(p);j(q);y(i=N;i--;p[i]*=q[i]);j(p,1);y(i=0;i<N;i++)if(o=real(p[i])+.5)l<<i<<" "<<o<<'\n';l<<'\n';}} | ^~~~ main.cpp: In function 'int main()': main.cpp:3:439: warning: suggest parentheses around assignment used as truth value [-Wparentheses] 3 | using namespace std;int N=1<<16,t,n,i,o,r;void j(auto&a,int q=0){auto b=a;y(r=n=a.size();r/=2;swap(a,b))y(i=0;i<n/2;i+=r)y(o=0;o<r;){auto u=a[i*2+o],v=polar(1.,2*M_PI/n*(q?-i:i))*a[i*2+o+r];b[i+o]=u+v;b[i+n/2+o++]=u-v;}y(auto&x:a)x/=q?n:1;}main(){fstream g("bacterii2.in"),l("bacterii2.out",ios::out);y(g>>t;t--;){vector p(N,0i),q=p;y(g>>n;n--;p[r]+=1)g>>r;y(g>>o;o--;q[r]+=1)g>>r;j(p);j(q);y(i=N;i--;p[i]*=q[i]);j(p,1);y(i=0;i<N;i++)if(o=real(p[i])+.5)l<<i<<" "<<o<<'\n';l<<'\n';}} | ~^~~~~~~~~~~~~~