View Compilation Error

0_0_37690728_29151.cpp: In function 'int query()':
0_0_37690728_29151.cpp:41:25: error: 'memset' was not declared in this scope
     memset(p,0,sizeof(p));
                         ^
0_0_37690728_29151.cpp: In function 'int main()':
0_0_37690728_29151.cpp:56:29: error: 'memset' was not declared in this scope
         memset(G,0,sizeof(G));
                             ^