View Compilation Error

0_0_23153670_18916.cpp:1:2: error: expected unqualified-id before 'for'
  for(register int i=beg[x];i;i=nex[i]){
  ^
0_0_23153670_18916.cpp:1:28: error: 'i' does not name a type
  for(register int i=beg[x];i;i=nex[i]){
                            ^
0_0_23153670_18916.cpp:1:30: error: 'i' does not name a type
  for(register int i=beg[x];i;i=nex[i]){
                              ^
0_0_23153670_18916.cpp:8:1: error: expected declaration before '}' token
 }
 ^