//UL, UR, R, LR, LL, L
#include<stdio.h>
#include<string.h>
int main(){
    int n,is,js,id,jd,c=0;
    char ans[1000]={""};
    scanf("%d",&n);
    scanf("%d%d%d%d",&is,&js,&id,&jd);
    if((is-id)%2!=0)
        printf("Impossible\n");
    else if((js-(is-id)/2-jd)%2!=0)
        printf("Impossible\n");
    else{
        while(is!=id || js!=jd){
            if(is-id>0 && js-jd>0){
                strcat(ans,"UL ");
                is-=2;
                js-=1;
            }else if(is-id>0 && js-jd<0){
                strcat(ans,"UR ");
                is-=2;
                js+=1;
            }else if(is-id>0 && js-jd==0){
                strcat(ans,"UL ");
                is-=2;
                js-=1;
            }else if(is-id==0 && js-jd<0){
                strcat(ans,"R ");
                js+=2;
            }else if(is-id<0 && js-jd<0){
                strcat(ans,"LR ");
                is+=2;
                js+=1;
            }else if(is-id<0 && js-jd>0){
                strcat(ans,"LL ");
                is+=2;
                js-=1;
            }else if(is-id<0 && js-jd==0){
                strcat(ans,"LR ");
                is+=2;
                js+=1;
            }else if(is-id==0 && js-jd>0){
                strcat(ans,"L ");
                js-=2;
            }
            c++;
        }
        printf("%d\n",c);
        printf("%s",ans);
    }
}