View Compilation Error

0_0_13807110_17684.cpp: In function 'int main()':
0_0_13807110_17684.cpp:57:28: error: 'memset' was not declared in this scope
 memset(num , 0 ,sizeof(num));
                            ^
0_0_13807110_17684.cpp:139:25: error: 'pow' was not declared in this scope
 printf(" %.lf",pow(3.0,i));
                         ^
0_0_13807110_17684.cpp:154:41: error: 'pow' was not declared in this scope
 if(num[i] == 1) printf(" %.lf",pow(3.0,i));
                                         ^