View Compilation Error

0_0_20857597_8727.cpp:18:15: error: no matching function for call to 'Edge::Edge()'
 Edge edge[maxm]; 
               ^
0_0_20857597_8727.cpp:18:15: note: candidates are:
0_0_20857597_8727.cpp:16:2: note: Edge::Edge(int, int, int, int)
  Edge (int _to,int _capa,int _flow,int _next):to(_to),capa(_capa),flow(_flow),next(_next){}
  ^
0_0_20857597_8727.cpp:16:2: note:   candidate expects 4 arguments, 0 provided
0_0_20857597_8727.cpp:14:8: note: constexpr Edge::Edge(const Edge&)
 struct Edge{
        ^
0_0_20857597_8727.cpp:14:8: note:   candidate expects 1 argument, 0 provided
0_0_20857597_8727.cpp:14:8: note: constexpr Edge::Edge(Edge&&)
0_0_20857597_8727.cpp:14:8: note:   candidate expects 1 argument, 0 provided