c++从字符数组中的特定索引拉取有符号整数

#include <iostream>
#include <string>

int main() {
    char charArray[] = "12345";
    int startIndex = 1;
    int length = 3;
    
    std::string substring(charArray + startIndex, length);
    
    try {
        int result = std::stoi(substring);
        std::cout << "Extracted signed integer: " << result << std::endl;
    } catch (const std::exception& e) {
        std::cout << "Failed to extract signed integer: " << e.what() << std::endl;
    }
    
    return 0;
}