[原创代码] 欧拉计划016-What is the sum of the digits of the number 2^1000?

codegay

欧拉计划016-What is the sum of the digits of the number 2^1000?

"""
python 欧拉计划016-What is the sum of the digits of the number 2^1000?
https://projecteuler.net/problem=16
2016年4月14日 13:37:24 codegay
"""
 
print(sum(map(int,list(str(2**1000)))))
 
"""
1366
[Finished in 0.1s]
"""COPY

codegay

#可以省掉list
sum(map(int,str(2**1000)))COPY

codegay

projecteuler.net 网站，别人贴的julia一行流

sum(digits(big(2)^1000))COPY

happy886rr

纯批处理，3.86秒，已经是极限速度了。

@echo off&setlocal enabledelayedexpansion
set "F[1]=00000002"
for /l %%i in (2 1 38) do (
	set "F[%%i]=00000000"
)
for /l %%i in (2 1 1000) do (
	set add=0
	for /l %%j in (1 1 38) do (
		set/a tmp=1!F[%%j]!+1!F[%%j]!+add
		set/a add=!tmp:~0,1!-2
		set F[%%j]=!tmp:~1!
	)
)
for /l %%i in (1 1 38) do (
	for /l %%j in (0 1 7) do (
		set/a "sum+=!F[%%i]:~%%j,1!"
	)
)
set/p=数字2的1000次方的各位数字之和为：!sum!COPY

----------------------------------------------------------------
python 0.05秒

# Python EulerPJ-016:What is the sum of the digits of the number 2^1000?
q=2**1000;r=0
while q>0:
	r+=q%10;q//=10
print(r)COPY

二进制位操作不需要时间。