检查给定的字符串是否为回文c++迭代法

#include <iostream>
#include <string>
#include <algorithm>

bool isPalindrome(const std::string& str) {
    std::string lowercaseStr = str;
    std::transform(lowercaseStr.begin(), lowercaseStr.end(), lowercaseStr.begin(), ::tolower);
    
    int left = 0;
    int right = lowercaseStr.length() - 1;
    
    while (left < right) {
        if (lowercaseStr[left] != lowercaseStr[right]) {
            return false;
        }
        
        left++;
        right--;
    }
    
    return true;
}

int main() {
    std::string input;
    std::cout << "Enter a string: ";
    std::cin >> input;
    
    if (isPalindrome(input)) {
        std::cout << "The string is a palindrome." << std::endl;
    } else {
        std::cout << "The string is not a palindrome." << std::endl;
    }
    
    return 0;
}