View Compilation Error

0_0_17836664_22981.cpp:1:1: error: 'rev' does not name a type
 rev[1]=1; for (int i=2;i<=n;++i) rev[i]=1LL*(mod-(mod/i))*rev[mod%i]%mod;
 ^
0_0_17836664_22981.cpp:1:11: error: expected unqualified-id before 'for'
 rev[1]=1; for (int i=2;i<=n;++i) rev[i]=1LL*(mod-(mod/i))*rev[mod%i]%mod;
           ^
0_0_17836664_22981.cpp:1:24: error: 'i' does not name a type
 rev[1]=1; for (int i=2;i<=n;++i) rev[i]=1LL*(mod-(mod/i))*rev[mod%i]%mod;
                        ^
0_0_17836664_22981.cpp:1:29: error: expected unqualified-id before '++' token
 rev[1]=1; for (int i=2;i<=n;++i) rev[i]=1LL*(mod-(mod/i))*rev[mod%i]%mod;
                             ^