View Compilation Error

0_0_13151596_16523.cpp: In function 'void FFT(std::complex<double>*, int, int)':
0_0_13151596_16523.cpp:34:51: error: lvalue required as left operand of assignment
  if(o < 0) for(int i = 0; i < l; i++) y[i].real() /= l;
                                                   ^
0_0_13151596_16523.cpp: In function 'int main()':
0_0_13151596_16523.cpp:57:61: error: lvalue required as left operand of assignment
   for(int i = 0; i < len; i++) x1[i] = sum[i], x1[i].imag() = 0;//, cout<<i<<" "<<sum[i]<<" "<<x1[i]<<endl;
                                                             ^