Mã chấm: 269830

Main.cc: In function ‘int main()’:
Main.cc:12:22: error: lvalue required as left operand of assignment
     pi+=(-1)^i/(2*i+1);}
                      ^
Main.cc:13:28: error: lvalue required as left operand of assignment
   pi = round(pi * 100000)/ 100000;
                            ^~~~~~
Main.cc:8:8: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&n);
   ~~~~~^~~~~~~~~