View Compilation Error

0_0_39561829_11323.cpp: In function 'int main()':
0_0_39561829_11323.cpp:16:47: error: 'b' was not declared in this scope
   16 |                         printf("%.6f",1+log(x/b));
      |                                               ^
0_0_39561829_11323.cpp:16:41: error: 'log' was not declared in this scope; did you mean 'long'?
   16 |                         printf("%.6f",1+log(x/b));
      |                                         ^~~
      |                                         long