foo.cc: In constructor 'node::node(int, int, int, int)':
foo.cc:39:27: warning: 'node::maxn' will be initialized after [-Wreorder]
   39 |         int sum,lmax,rmax,maxn;
      |                           ^~~~
foo.cc:39:13: warning:   'int node::sum' [-Wreorder]
   39 |         int sum,lmax,rmax,maxn;
      |             ^~~
foo.cc:40:9: warning:   when initialized here [-Wreorder]
   40 |         node(int a = 0,int b = 0,int c = -2000000000,int d = 0):lmax(a),rmax(b),maxn(c),sum(d){}
      |         ^~~~

[Hydro](https://hydro.ac)提供评测服务