/in/foo.cc: In function 'void update(int)':
/in/foo.cc:13:17: error: 'max' was not declared in this scope
      tree[k].lm=max(tree[k<<1].lm,tree[k<<1].sum+tree[k<<1|1].lm);
                 ^~~
/in/foo.cc: In function 'data1 ask(int, int, int)':
/in/foo.cc:37:14: error: 'max' was not declared in this scope
     a.mx=max(max(g.mx,h.mx),g.rm+h.lm);
              ^~~
/in/foo.cc:37:10: error: 'max' was not declared in this scope
     a.mx=max(max(g.mx,h.mx),g.rm+h.lm);
          ^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:64:28: error: 'swap' was not declared in this scope
                     if(x>y)swap(x,y);
                            ^~~~