View Compilation Error

0_0_14287827_8493.cpp: In function 'int pd(int)':
0_0_14287827_8493.cpp:4:14: error: 'sqrt' was not declared in this scope
  int k=sqrt(x);
              ^
0_0_14287827_8493.cpp:5:6: error: 'i' was not declared in this scope
  for(i=2;i<=k;i++)
      ^
0_0_14287827_8493.cpp: In function 'int main()':
0_0_14287827_8493.cpp:23:8: error: 'i' was not declared in this scope
    for(i=1;i<10000;i++)
        ^
0_0_14287827_8493.cpp:32:17: error: 'k' was not declared in this scope
   printf("%d\n",k);
                 ^