16:忽略大小写的字符串比较

问题遇到的现象和发生背景

用代码块功能插入代码，请勿粘贴截图

我想要达到的结果

这里哪里有漏洞吗，十个输入输出样例对了九个
16:忽略大小写的字符串比较

#include<iostream>
#include<string>
#include<string.h>
#include<stdio.h>
using namespace std;
int main()
{
    string arr1, arr2;
    getline(cin, arr1);
    getline(cin, arr2);
    int len1 = arr1.size();
    int len2 = arr2.size();
    if (len1 < len2)
    {
        cout << "<" << endl;
        return 0;
    }
    else if (len1 > len2)
    {
        cout << ">" << endl;
        return 0;
    }
    else
    {
        for (int i = 0; i < len1; i++)
        {
            if (arr1[i] <= 122 && arr1[i] >= 97)
                arr1[i] -= 32;
        }
        for (int i = 0; i < len1; i++)
        {
            if (arr2[i] <= 122 && arr2[i] >= 97)
                arr2[i] -= 32;
        }
        for (int i = 0; i < len1; i++)
        {
            if ((int)arr1[i] == (int)arr2[i])
                continue;
            if ((int)arr1[i] > (int)arr2[i])
            {
                cout << ">" << endl;
                return 0;
            }
            if ((int)arr1[i] < (int)arr2[i])
            {
                cout << "<" << endl;
                return 0;
            }
        }
        cout << "=" << endl;
    }
    return 0;
}

toupper 或者 tolower

感谢邀请，把代码贴出来，别贴截图，截图看不清