蓝桥杯 数的读法（判断 函数）

#include <bits/stdc++.h>
using namespace std;
string s;
string a[20]={"","","shi","bai","qian","wan","shi","bai","qian","yi","shi"};
string b[20]={"ling","yi","er","san","si","wu","liu","qi","ba","jiu"};
int main()
{
    cin>>s;
    int len=s.length(),ans1,ans2;
    for(int i=0;i<len;i++){
        int j=s[i]-‘0‘;
        if(len-i>=9)ans1=1;
        if(len-i<9&&len-i>=5)ans2=1;//判断千万~万是否有位数

        if(j==0){
            if(i<len-1&&s[i+1]!=‘0‘)cout<<b[j]<<" ";//ling
            if(((len-i==9)&&ans1) || (len-i==5)&&ans2)
                cout<<a[len-i]<<" ";}
        else{
            if((len-i==2||len-i==6||len-i==10)&&j==1&&i==0)
                cout<<a[len-i]<<" ";//十亿、十万、十
            else cout<<b[j]<<" "<<a[len-i]<<" ";}
    }
    printf("\n");
}