foo.cpp:1:1: error: 'include' does not name a type
 include<cstdio>
 ^
foo.cpp: In function 'int kruskal()':
foo.cpp:13:16: error: 'sort' was not declared in this scope
  sort(r,r+m,cmp); 
                ^
foo.cpp: In function 'int main()':
foo.cpp:30:25: error: 'scanf' was not declared in this scope
  scanf("%d%d%d",&n,&m,&k); 
                         ^
foo.cpp:34:27: error: 'printf' was not declared in this scope
  if(ans>0) printf("%d",ans); 
                           ^
foo.cpp:35:25: error: 'printf' was not declared in this scope
  else printf("No Answer"); 
                         ^