#include<stdio.h>#include<string.h>#include<stdlib.h>#include<ctype.h>#define LT(x) ((x<<2)|1)#define RT(x) ((x<<2)|2)#define LB(x) ((x<<2)|3)#define RB(x) ((x<<2)+4)#define M 1024typedef struct{char c;int lt,rt,lb,rb;}TN;TN T[M*M];unsigned char map[M][M>>3];char tmp[M];void Create(int ix,int t,int l,int s){int m;if(s==1)T[ix].c=map[t][l>>3]&(1<<(l&7))?'B':'W';else{m=s>>1;Create(LT(ix),t,l,m);Create(RT(ix),t,l+m,m);Create(LB(ix),t+m,l,m);Create(RB(ix),t+m,l+m,m);if(T[LT(ix)].c==T[RT(ix)].c&&T[LT(ix)].c==T[LB(ix)].c&&T[LT(ix)].c==T[RB(ix)].c)T[ix].c=T[LT(ix)].c;else T[ix].c='Q';}}void Traverse(int ix){putchar(T[ix].c);if(T[ix].c=='Q'){Traverse(LT(ix));Traverse(RT(ix));Traverse(LB(ix));Traverse(RB(ix));}}int main(){int n,i,j;scanf("%s%s%d ",tmp,tmp,&n);gets(tmp);gets(tmp);for(i=0;i<n;i++){for(j=0;j<n>>3;j++){scanf("%x,",&map[i][j]);}}Create(0,0,0,n);printf("%dn",n);Traverse(0);puts("");return 0;}
