View Compilation Error

0_0_6719551_11513.cpp:90: error: expected unqualified-id before '[' token
0_0_6719551_11513.cpp: In member function `std::pair<bool, int> cost_flow::SSP()':
0_0_6719551_11513.cpp:42: error: `v' undeclared (first use this function)
0_0_6719551_11513.cpp:42: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6719551_11513.cpp: In member function `int cost_flow::dfs(int, int)':
0_0_6719551_11513.cpp:50: error: `v' undeclared (first use this function)