View Compilation Error

0_0_24115296_12723.cpp: In function 'int main()':
0_0_24115296_12723.cpp:16:27: error: 'memset' was not declared in this scope
   memset(in, 0, sizeof(in));
                           ^
0_0_24115296_12723.cpp:18:22: error: 'strlen' was not declared in this scope
   int ilen = strlen(i);
                      ^