include<cstdio>
#include<cstring>
#include<queue>
#include<string>
#include<iostream>
using namespace std;
int a,b,c;
int v[111][111];
struct node
{
    int x;
    int y;
    int step;
    string s;
};
int bfs()
{
    queue<node>Q;
    int l=1;
    node p,q;
    p.x=0;
    p.y=0;
    p.step=0;
    p.s+='0';
    Q.push(p);
    v[0][0]=1;
    while(!Q.empty())
    {
        p=Q.front();
        Q.pop();
        //printf("%d %d  %d  ",p.x,p.y,p.step);
        //cout<<p.s<<endl;
        if(p.x==c||p.y==c)
        {
            cout<<p.step<<endl;
            for(int i=0; p.s[i]!='\0'; i++)
            {
                if(p.s[i]=='1')
                {
                    printf("FILL(1)\n");
                }
                if(p.s[i]=='2')
                {
                    printf("DROP(1)\n");
                }
                if(p.s[i]=='3')
                {
                    printf("POUR(1,2)\n");
                }
                if(p.s[i]=='4')
                {
                    printf("FILL(2)\n");
                }
                if(p.s[i]=='5')
                {
                    printf("DROP(2)\n");
                }
                if(p.s[i]=='6')
                {
                    printf("POUR(2,1)\n");
                }

            }
            return 1;
        }
        else
        {
            int xx=a,yy=b;
            q.x=p.x+(xx-p.x);  // 把 1 倒满   记为 1
            q.y=p.y;
            q.s=p.s+'1';
            q.step=p.step+1;
            if(v[q.x][q.y]==0)
            {
                v[q.x][q.y]=1;
                Q.push(q);

            }
            q.x=0; //把 1 倒掉 记为 2
            q.y=p.y;
            q.s=p.s+'2';
            q.step=p.step+1;
            if(v[q.x][q.y]==0)
            {
                v[q.x][q.y]=1;
                Q.push(q);

            }
            if(p.x>=(yy-p.y))  // 把1倒给2   记为 3
            {
                q.x=p.x-(yy-p.y);
                q.y=p.y+(yy-p.y);
                q.step=p.step+1;
                q.s=p.s+'3';
                if(v[q.x][q.y]==0)
                {
                    v[q.x][q.y]=1;
                    Q.push(q);

                }
            }
            if(p.x<yy-p.y)   // 把1倒给2   记为 3
            {
                q.x=0;
                q.y=p.y+p.x;
                q.step=p.step+1;
                q.s=p.s+'3';
                if(v[q.x][q.y]==0)
                {
                    v[q.x][q.y]=1;
                    Q.push(q);

                }
            }
            q.x=p.x;    // 把2倒满  记为  4
            q.y=p.y+(yy-p.y);
            q.s=p.s+'4';
            q.step=p.step+1;
            if(v[q.x][q.y]==0)
            {
                v[q.x][q.y]=1;
                Q.push(q);

            }
            q.x=p.x;  //把2倒掉  记为 5
            q.y=0;
            q.s=p.s+'5';
            q.step=p.step+1;
            if(v[q.x][q.y]==0)
            {
                v[q.x][q.y]=1;
                Q.push(q);
            }
            if(p.y>=(xx-p.x))  //把2倒给1 记为  6
            {
                q.x=p.x+(xx-p.x);
                q.y=p.y-(xx-p.x);
                q.s=p.s+'6';
                q.step=p.step+1;

                if(v[q.x][q.y]==0)
                {
                    v[q.x][q.y]=1;
                    Q.push(q);

                }
            }
            else if(p.y<xx-p.x)
            {
                q.x=p.x+p.y;
                q.y=0;
                q.s=p.s+'6';
                q.step=p.step+1;
                if(v[q.x][q.y]==0)
                {
                    v[q.x][q.y]=1;
                    Q.push(q);

                }
            }
        }
    }
    return 0;
}
int main()
{
    while(~scanf("%d %d %d",&a,&b,&c))
    {
        memset(v,0,sizeof(v));
        int sum=bfs();
        if(sum==0)
            printf("impossible\n");
    }
}