[Previous line repeated 995 more times]RecursionError: maximum recursion depth exceeded

reason ： Recursion depth exceeded

solve ：

import sys
sys.setrecursionlimit(100000)

Encountered new problems ：Process finished with exit code -1073741571 (0xC00000FD)

reason ： Stack overflow

Usually windows The default stack size is 1024bytes

solve ：

1. It may be that the value of the local variable is too large , Change it to a global variable （ Pay attention to Out of function use global Statement ）

2. Tail recursion ：Python The interpreter is in a function call , A stack frame will be used to save the information of the currently called function , Such as input parameters 、 Return value space 、 Temporary storage space used to evaluate expressions 、 State information and output parameters saved during function call . So in recursive calls , Such unexecuted functions will occupy a large number of stack frames layer by layer . If you put the recursive call to the last step of function execution , Then finish this step , The stack frame of this function will be released , The new stack frame of the calling function will replace the previous stack frame , So no matter how many times the depth of the call is , Will only occupy a stack frame , Then there will be no stack overflow problem . This is tail recursion .

        The key ： The precondition is that nothing will be executed after the call , Therefore, what needs to be passed must be passed through parameter design in advance

        for example ： and

         The first is to multiply after each call n, there res It plays the same role , Due to tail recursion, the stack frame of each layer should be released , So pass res As a multiplication process

 3. Modify stack heap size ：

        python of use threading To carry out ：

if __name__ == '__main__':
    threading.stack_size(200000000)
    thread = threading.Thread(target=your_code)
    thread.start()