复制下面代码输入ABCDEF 1000
会发现13==13 为0

typedef long long ll;
string s;ll n;
ll sc(ll l){
    cout<<l<<endl;
    ll x;
    if(n>l){
        x=sc(2*l);
        if(x<l/2)return x;
    }
    else
        x=n;
    cout<<x<<" "<<l/2+1<<"___"<<(x==1/2+1)<<<endl;//这里13 13___0
    if(x==1/2+1){
        return l/2;
    }else{
        return l/2-(l-x)-1;
    }
}
int main(){
    cin>>s>>n;
    s='?'+s;
    ll q=sc(s.length()-1);
    //cout<<s[q]<<endl;
}