C++ stoi Function Error Fixes

When using the std::stoi function in C++ to convert a string to an integer, if an error occurs, you can try the following solutions:

1. Make sure the correct header file is included: Before using std::stoi, the header file needs to be included.
2. Check if the string is valid: the std::stoi function can only handle valid integer strings. If the string contains non-numeric characters, it will result in an error. You can use the std::isdigit function to check if the string contains only numeric characters.
3. Check if a string exceeds the integer range: The string converted by the std::stoi function must be within the range of integers, otherwise an error will be thrown. You can use the std::numeric_limits::min() and std::numeric_limits::max() functions to check the minimum and maximum values of integers to ensure the string does not exceed the range.
4. To handle exceptions: the std::stoi function throws a std::invalid_argument exception when conversion fails, which can be caught and handled using a try-catch statement. For example:

try {
    int num = std::stoi(str);
    // 处理转换成功的情况
} catch (const std::invalid_argument& e) {
    // 处理转换失败的情况
}

By using the methods mentioned above, the issue of errors in using the std::stoi function should be resolved. If the problem persists, please provide more information and code for a more specific analysis and solution.