View Compilation Error

762519_0_0_3569.cpp: In function `void DFS(int, int, int)':
762519_0_0_3569.cpp:36: error: `i' undeclared (first use this function)
762519_0_0_3569.cpp:36: error: (Each undeclared identifier is reported only once for each function it appears in.)
762519_0_0_3569.cpp:36: error: `j' undeclared (first use this function)