C++ question. Please fix my code to work as the instruction.

#includeiostream #include-loma nip> #include-cmath using namespace std; double arctanApprox (double x,double tol) int i-1; double d1; double sum-0; double prevsum-0; while(true) if ( i%2- 1) sum sum+(pow(x,d)/d); else sum sum+(pow(x,d)/d); if(abs (prevsum-sum)>tol; if(tol>tol; sum 16.0 arctanApprox (1.0/5.0,tol)-4.0*arctanApprox(1.0/239.0,tol); coutPi approximation : "