View Compilation Error

0_0_18313755_26842.cpp: In function 'int main()':
0_0_18313755_26842.cpp:47:54: error: lvalue required as left operand of assignment
       a[i].real()=a[i].imag()=b[i].real()=b[i].imag()=0;
                                                      ^
0_0_18313755_26842.cpp:52:28: error: lvalue required as left operand of assignment
          a[i*1500+j].real()=x[i][j];
                            ^
0_0_18313755_26842.cpp:57:39: error: lvalue required as left operand of assignment
           b[(i+300)*1500+j+300].real()=1/(1+sqrt(i*i+j*j));
                                       ^