View Compilation Error

0_0_39137416_7625.cpp: In function 'void solve(Node)':
0_0_39137416_7625.cpp:57:37: error: 'sqrt' was not declared in this scope; did you mean 'st'?
   57 |                         double xx = sqrt(1.0*(t.x - h[L].x)*(t.x - h[L].x));
      |                                     ^~~~
      |                                     st
0_0_39137416_7625.cpp:77:37: error: 'sqrt' was not declared in this scope; did you mean 'st'?
   77 |                         double xx = sqrt(1.0*(t.x - h[R].x)*(t.x - h[R].x));
      |                                     ^~~~
      |                                     st