View Compilation Error

0_0_26439634_27868.cpp: In function 'int main()':
0_0_26439634_27868.cpp:32:10: error: 'ans' was not declared in this scope
   memset(ans, 0, sizeof(ans));
          ^
0_0_26439634_27868.cpp:32:29: error: 'memset' was not declared in this scope
   memset(ans, 0, sizeof(ans));
                             ^