View Compilation Error

0_0_14653365_17619.cpp: In function 'void djstl(int, int)':
0_0_14653365_17619.cpp:9:22: error: 'memset' was not declared in this scope
  memset(s1,0,sizeof s);
                      ^
0_0_14653365_17619.cpp: In function 'int main()':
0_0_14653365_17619.cpp:35:23: error: 'memset' was not declared in this scope
   memset(d,63,sizeof d);
                       ^