View Compilation Error

0_0_23506174_14367.cpp: In function 'void dfs(int, int, int)':
0_0_23506174_14367.cpp:18:9: error: 'xx' was not declared in this scope
         xx = nx + Step[i][0];
         ^
0_0_23506174_14367.cpp:19:9: error: 'yy' was not declared in this scope
         yy = ny + Step[i][1];
         ^