View Compilation Error

0_0_38552590_7031.cpp: In function 'int main()':
0_0_38552590_7031.cpp:9:29: error: 'memset' was not declared in this scope
         memset(s,0,sizeof(s));
                             ^
0_0_38552590_7031.cpp:11:19: error: 'strlen' was not declared in this scope
         l=strlen(s);
                   ^