View Compilation Error

0_0_14300052_23212.cpp: In function 'int main()':
0_0_14300052_23212.cpp:31:37: error: 'strlen' was not declared in this scope
         scanf("%s",s+1);L=strlen(s+1);
                                     ^
0_0_14300052_23212.cpp:35:28: error: 'memset' was not declared in this scope
         memset(F,0,sizeof F);memset(G,0,sizeof G);
                            ^