#include<stdio.h>
#include<string.h>
int main (){
    int C,Q;
    if(scanf("%d%d",&C,&Q)!=2||C<1||C>1000||Q>50000){puts("Invalid input");return 0;}
    int a[1000],f=0,n=0;
    char cmd[20];
    while(Q-- && scanf("%s",cmd)==1){
        if(!strcmp(cmd,"PUSHFRONT")){
            int x;if(scanf("%d",&x)!=1||x<1||x>1000000|| n==C){puts("Invalid input");return 0;}
            f=(f-1+C)%c;a[f]=x;n++;
        }else if(!strcmp(cmd,"PUSHBACK")){
            int x;if(scanf("%d",&x)!=1||x<1||x>1000000|| n==C){puts("Invalid input");return 0;}
            a[(f+n)%C]=x; n++;
        }else if(!strcmp(cmd,"POPFRONT")){
            if (n){puts("Removed"); f=f(f+1)%C; n--;}else puts ("Empty");
        }else if(!strcmp(cmd,"POPBACK")){
            if (n){puts("Removed");n--;}else puts ("Empty");
        }else if(!strcmp(cmd,"FRONT")){
            if (n) printf("%d\n",a[f]);else puts("Empty");
        }else if(!strcmp(cmd,"BACK")){
            if (n) printf("%d\n",a[(f+n-1)%C]);else puts("Empty");
        }else if(!strcmp(cmd,"ISEMPTY")){
            puts(n?"NO":"YES");
        }else if(!strcmp(cmd,"ISFULL")){
            puts(n==C?"YES":"NO");
        }else{puts{"Invalid input");return 0;}
            
    }
    return 0;
}