View Compilation Error

0_0_17151938_19249.cpp: In function 'bool cmp(const Data&, const Data&)':
0_0_17151938_19249.cpp:7:32: error: 'strcmp' was not declared in this scope
  else return strcmp(d1.ID,d2.ID)<0?1:0;
                                ^
0_0_17151938_19249.cpp: In function 'int main()':
0_0_17151938_19249.cpp:15:26: error: 'memset' was not declared in this scope
   memset(d,NULL,sizeof(d));
                          ^