in the 191667514 problem 1778B - The Forbidden Permutation, the problem promises that p is a permutation, but in fact, when I output p's value in pretest 2 case 120 by using following code:

vector<int> p(n+10);
vector<int> a(m+10);
if(cnt==120)
	cout<<"Case120:"<<n<<" "<<m<<endl;
rep(i,1,n,1){
        cin>>p[i];
	if(cnt==120)
		cout<<p[i]<<" ";
}

the output is:

Case120:2 1
3 3 
1 
4557430888798830399

the p is not a permutation, what happens?