def TextEditor(ops):
    s=''
    done=[]
    for i in ops:
        if i[0]=='1':
            s=s+(i[1])
            done.append(i)
        elif i[0]=='2':
            e=s[(len(s)-int(i[1])):len(s)]
            s=s[0:(len(s)-int(i[1]))]
            i.append(e)
            done.append(i)
        elif i[0]=='3':
            print(s[int(i[1])-1])
        elif i[0]=='4':
            u=done[-1]
            if u[0]=='1':
                s=s[0:(len(s)-len(u[1]))]
            elif u[0]=='2':
                s=s+(u[2])
            done.pop()
    return
    
    
q=int(input()) 
ops=[]
for i in range(q):
    ops.append(input().split())
TextEditor(ops)