运用多线程的方法计算pi的值。通过公式法和面积法实现。可以通过调整线程数和数据的运算规模来计算pi，计算不同线程之间的性能差异。-Calculated using multi-threaded the value of pi. Area through the formula and method implementation. You can adjust the number of threads and data operations to calculate the size of pi