View Compilation Error

0_0_12822077_29802.cpp: In function `void dfs(int, int, int)':
0_0_12822077_29802.cpp:40: error: `n' undeclared (first use this function)
0_0_12822077_29802.cpp:40: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_12822077_29802.cpp:40: error: `m' undeclared (first use this function)