View Compilation Error

0_0_20779473_19091.cpp:1:2: error: expected unqualified-id before 'for'
  for(int i=1;i*i<=n;i++)
  ^
0_0_20779473_19091.cpp:1:14: error: 'i' does not name a type
  for(int i=1;i*i<=n;i++)
              ^
0_0_20779473_19091.cpp:1:21: error: 'i' does not name a type
  for(int i=1;i*i<=n;i++)
                     ^