View Compilation Error

0_0_16973633_14525.cpp: In function 'int main()':
0_0_16973633_14525.cpp:6:28: error: 'memset' was not declared in this scope
     memset (b,true,10000000);
                            ^
0_0_16973633_14525.cpp:12:36: error: 'strlen' was not declared in this scope
                      int s=strlen(a);
                                    ^