View Compilation Error

0_0_38611505_6446.cpp: In function 'int main(int, const char**)':
0_0_38611505_6446.cpp:24:28: error: 'sqrt' was not declared in this scope
         double leq = 300 * sqrt(2.0) / v1;
                            ^~~~
0_0_38611505_6446.cpp:24:28: note: suggested alternative: 'qsort'
         double leq = 300 * sqrt(2.0) / v1;
                            ^~~~
                            qsort