foo.cc: In function 'int find(int)':
foo.cc:15:18: error: 'fa' was not declared in this scope; did you mean 'f'?
   15 |      else return fa[x]=find(f[x]);
      |                  ^~
      |                  f
foo.cc: In function 'int main()':
foo.cc:26:16: error: 'xx' was not declared in this scope
   26 |    int aa=find(xx);
      |                ^~
foo.cc:27:16: error: 'yy' was not declared in this scope
   27 |    int bb=find(yy);
      |                ^~
foo.cc:24:8: warning: unused variable 'a' [-Wunused-variable]
   24 |    int a=edge[i].x;
      |        ^
foo.cc:25:8: warning: unused variable 'b' [-Wunused-variable]
   25 |    int b=edge[i].y;
      |        ^
foo.cc:19:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |  scanf("%d%d%d",&n,&m,&k);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:20:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |  for(int i=1;i<=m;i++) scanf("%d%d%d",&edge[i].x,&edge[i].y,&edge[i].w);
      |                        ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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