View Compilation Error

0_0_32855533_26133.cpp: In function 'void prime()':
0_0_32855533_26133.cpp:10:24: error: 'memset' was not declared in this scope
  memset(f, 0, sizeof(f));
                        ^
0_0_32855533_26133.cpp: In function 'int main()':
0_0_32855533_26133.cpp:79:25: error: 'memset' was not declared in this scope
   memset(b, 0, sizeof(b));
                         ^