笨蛋脑子的解法呜呜呜

#include<iostream>
using namespace std;
int main()
{
    double num;
    cin>>num;
    int a;
    a=int(num);//123
    int hundred=a/100;//1
    int b=hundred*100;//100
    int c=a-b;//23
    int d=c/10;//2
    int e=c%10;//3
    double f=num-double(a);//0.4
    double bai=f*10;//4
    double ten=double(e)/10;//0.3
    double one=double(d)/100;//0.02
    double zero=double(hundred)/1000;//0.001
    double whole=bai+ten+one+zero;
    cout<<whole<<endl;
    return 0;
}