View Compilation Error

0_0_13257134_32189.cpp: In function 'int main()':
0_0_13257134_32189.cpp:22:29: error: 'memset' was not declared in this scope
         memset(A,0,sizeof(A));
                             ^
0_0_13257134_32189.cpp:23:21: error: 'strlen' was not declared in this scope
         len=strlen(s);
                     ^