View Compilation Error

0_0_29138196_25150.cpp: In function 'int main()':
0_0_29138196_25150.cpp:11:23: error: 'memset' was not declared in this scope
   memset(s,0,sizeof(s));
                       ^
0_0_29138196_25150.cpp:15:18: error: 'sort' was not declared in this scope
   sort(s,s+30,cmp);
                  ^