View Compilation Error

0_0_17131075_21416.cpp: In function 'bool cmp(nameNode*, nameNode*)':
0_0_17131075_21416.cpp:56:33: error: '::strcmp' has not been declared
     else if(x->age == y->age && ::strcmp(x->name,y->name)<0  )
                                 ^
0_0_17131075_21416.cpp: In function 'int main()':
0_0_17131075_21416.cpp:74:44: error: 'memset' was not declared in this scope
         memset(peoples,NULL,sizeof(peoples));
                                            ^