View Compilation Error

0_0_38829662_21596.cpp: In function 'int main()':
0_0_38829662_21596.cpp:21:45: error: 'fabs' was not declared in this scope; did you mean 'labs'?
   21 |                 if(cal(x0)<=y0||cal(x1)>y2||fabs(cal(x1)-y0)<0.0000001||cal(2*x1-x0)>=y0)
      |                                             ^~~~
      |                                             labs