为什么我的字符串倒序无法运行 求解答

Question

#include <iostream>
using namespace std;
string invert(string s)
{
    char temp='a';
    int start=0;
    int end=sizeof(s)/sizeof(s[0])-1;
    while(start<end)
    { temp=s[start];
        s[start]=s[end];
        s[end]=temp;
        start++;
        end--;
    }
    return s;
}
int main()
{
    int n;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        string x;
        cin>>x;
        cout<<invert(x)<<endl;
    }
    return 0;
}

![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/04778386879613.png "#left")

Answer 1

int end=sizeof(s)/sizeof(s[0])-1;
string应该用s.length获取长度