View Compilation Error

0_0_25457493_22433.cpp: In function 'void dfs(int, int)':
0_0_25457493_22433.cpp:12:16: error: 'm' was not declared in this scope
   if(0<=dx&&dx<m&&0<=dy&&dy<n&&c[dx][dy]=='@')
                ^
0_0_25457493_22433.cpp:12:29: error: 'n' was not declared in this scope
   if(0<=dx&&dx<m&&0<=dy&&dy<n&&c[dx][dy]=='@')
                             ^