src.cpp:1:1: error: expected unqualified-id before 'for'
for (i=1;i<=sqrt(n);i++)
^
src.cpp:1:10: error: 'i' does not name a type
for (i=1;i<=sqrt(n);i++)
^
src.cpp:1:21: error: 'i' does not name a type
for (i=1;i<=sqrt(n);i++)
^