/in/foo.cc: In function 'int main()':
/in/foo.cc:30:2: error: expected initializer before 'for'
  for(int k= 0;k<n;k++){
  ^
/in/foo.cc:30:15: error: 'k' was not declared in this scope
  for(int k= 0;k<n;k++){
               ^