間違いを指摘してください
#include <iostream>
#include <algorithm>
#include <iomanip>
#include <string>
#include <cmath>
using namespace std;
int main(){
int a,b;
double i;
string op;
cin>>a>>op>>b;
if(op == "+"){
i = a+b;
} else if(op == "-"){
i = a-b;
} else if(op == "*"){
i = a*b;
} else if(op == "/"){
i =(double)a/b;
} else{
return 0;
}
cout<<setprecision( 6 )<<i<<endl;
return 0;
}