原理可参考:https://blog.csdn.net/qq_19782019/article/details/85621386
''' @param base 底数 @param power 指数 @return res 求幂结果的最后3位数 ''' def fast_power(base, power): res = 1 while power > 0: if power % 2 == 1: res = res * base % 1000 power = power // 2 base = base * base % 1000 return res % 1000 print(fast_power(2,1000000000))