输出时多一个空字符怎么解决

#include<iostream>
#include<string>

using namespace std;

int main() {
    int num;
    cin >> num;
    string str = to_string(num);
    string text = "";
    for (int n = str.length(); n >= 0;n--){
        text += str[n];
    }

    cout << text<< endl;;

    return 0;
}

从str.length()-1开始循环