Compilare: main.cpp:1:2: warning: #import is a deprecated GCC extension [-Wdeprecated] #import<bits/stdc++.h> ^~~~~~ main.cpp:2:81: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] using namespace std;vector<bool>V[20];bool A[1<<19];int N,i,k,j,val;char c;main(){ifstream cin("string.in");ofstream cout("string.out");cin>>N;for(i=0;cin>>c;i++)A[i]=c=='a';for(k=1,val;k<=19;k++){val=0;V[k].reserve(1<<k);for(i=0;i<k-1;i++)val<<=1,val+=A[i];for(i=k-1;i<N;i++)val<<=1,val&=((1<<k)-1),val+=A[i],V[k][val]=1;}for(k=1;k<=19;k++)for(i=0;i<(1<<k);i++)if(!V[k][i]){cout<<k<<'\n';for(j=k-1;j>=0;j--)cout<<((1<<j)&i?'a':'b');}} ^ main.cpp: In function 'int main()': main.cpp:2:186: warning: right operand of comma operator has no effect [-Wunused-value] using namespace std;vector<bool>V[20];bool A[1<<19];int N,i,k,j,val;char c;main(){ifstream cin("string.in");ofstream cout("string.out");cin>>N;for(i=0;cin>>c;i++)A[i]=c=='a';for(k=1,val;k<=19;k++){val=0;V[k].reserve(1<<k);for(i=0;i<k-1;i++)val<<=1,val+=A[i];for(i=k-1;i<N;i++)val<<=1,val&=((1<<k)-1),val+=A[i],V[k][val]=1;}for(k=1;k<=19;k++)for(i=0;i<(1<<k);i++)if(!V[k][i]){cout<<k<<'\n';for(j=k-1;j>=0;j--)cout<<((1<<j)&i?'a':'b');}} ^