View Compilation Error

0_0_18313137_15281.cpp: In constructor 'node::node()':
0_0_18313137_15281.cpp:13:32: error: 'memset' was not declared in this scope
   memset(next,NULL,sizeof(next));
                                ^
0_0_18313137_15281.cpp: In function 'int query(node*)':
0_0_18313137_15281.cpp:65:36: error: 'strlen' was not declared in this scope
  int i=0,cnt=0,index,len=strlen(str);
                                    ^