terminate called after throwing an instance of 'std::runtime_error

This error message indicates that a C++ program has encountered an exception of type std::runtime_error and that the exception was not caught by any of the program's exception handlers. The program has therefore terminated abruptly.

std::runtime_error is a standard exception class that is typically used to indicate some kind of runtime error condition, such as a file not found, a division by zero, or an out-of-memory condition. When such an error occurs, the program should catch the exception and handle it appropriately. If the exception is not caught, the program will terminate and display the error message you have seen.

To fix the error, you need to look at the code and identify where the std::runtime_error exception is being thrown. Then, you need to add an appropriate catch block to handle the exception and prevent the program from terminating.