View Compilation Error

0_0_32787604_20096.cpp: In function 'void calsiz(int, int, int)':
0_0_32787604_20096.cpp:12:15: error: 'head' was not declared in this scope
     for(int i=head[u];i;i=eg[i].to){
               ^
0_0_32787604_20096.cpp:12:27: error: 'eg' was not declared in this scope
     for(int i=head[u];i;i=eg[i].to){
                           ^