#include<cstdio> #include<cmath> #include<queue> #include<stack> #include<cstring> #include<iostream> #include<algorithm> using namespace std; int t,n; int main() { int i,j,k; cin>>t; char op[10],io[10]; while(t--) { scanf("%d%s",&n,op); if(op[2]=='F') { queue<int> q; while(n--) { scanf("%s",io); if(io[0]=='I') { int temp; scanf("%d",&temp); q.push(temp); } else if(io[0]=='O') { if(q.empty()) { printf("None "); } else { int temp=q.front(); q.pop(); printf("%d ",temp); } } } } else if(op[2]=='L') { stack<int> q; while(n--) { scanf("%s",io); if(io[0]=='I') { int temp; scanf("%d",&temp); q.push(temp); } else if(io[0]=='O') { if(q.empty()) { printf("None "); } else { int temp=q.top(); q.pop(); printf("%d ",temp); } } } } } return 0; }