View Compilation Error

0_0_5158095_24978.cpp: In function `void DFS(int, int, int, int)':
0_0_5158095_24978.cpp:22: error: `x' undeclared (first use this function)
0_0_5158095_24978.cpp:22: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_5158095_24978.cpp:22: error: expected `;' before "if"