View Compilation Error

0_0_17448650_31397.cpp: In function 'int bfs()':
0_0_17448650_31397.cpp:26:5: error: 'vis' was not declared in this scope
     vis[0][0][0]=1;
     ^
0_0_17448650_31397.cpp: In function 'int main()':
0_0_17448650_31397.cpp:81:15: error: 'vis' was not declared in this scope
        memset(vis,0,sizeof(vis));
               ^