View Compilation Error

0_0_36177758_843.cpp: In function 'void cal_distance(int*)':
0_0_36177758_843.cpp:3:78: error: 'sqrt' was not declared in this scope
  float a = sqrt((d[2] - d[0]) * (d[2] - d[0]) + (d[3] - d[1]) * (d[3] - d[1]));
                                                                              ^
0_0_36177758_843.cpp:4:2: error: 'cout' was not declared in this scope
  cout.setf(ios_base::fixed, ios_base::floatfield);
  ^
0_0_36177758_843.cpp:4:12: error: 'ios_base' has not been declared
  cout.setf(ios_base::fixed, ios_base::floatfield);
            ^
0_0_36177758_843.cpp:4:29: error: 'ios_base' has not been declared
  cout.setf(ios_base::fixed, ios_base::floatfield);
                             ^
0_0_36177758_843.cpp:5:12: error: 'ios_base' has not been declared
  cout.setf(ios_base::showpoint);
            ^
0_0_36177758_843.cpp:7:15: error: 'endl' was not declared in this scope
  cout << a << endl;;
               ^
0_0_36177758_843.cpp: In function 'int main()':
0_0_36177758_843.cpp:12:9: error: 'cin' was not declared in this scope
  while (cin >> d[0] >> d[1] >> d[2] >> d[3])
         ^