View Compilation Error

0_0_12818558_26571.cpp:11: error: expected constructor, destructor, or type conversion before '<' token
0_0_12818558_26571.cpp:11: error: expected `,' or `;' before '<' token
0_0_12818558_26571.cpp: In function `void DFS(Node*)':
0_0_12818558_26571.cpp:42: error: `res' undeclared (first use this function)
0_0_12818558_26571.cpp:42: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_12818558_26571.cpp: In function `int main()':
0_0_12818558_26571.cpp:49: error: `res' undeclared (first use this function)