#前几次做的时候sum_add的位置放错了。
#sum_add应该在第i次开始前清零
#如果不用等差数列求和公式:
#先求出要加的项,再求出前n项和
amount = int(input("请输入需要输入的项:"))
#我先找出第i次循环的最大值,每次最大值将前一次的求和加上本次的求和
#第i次循环的最大值记作i
i = 0
#它的和记作sum
sum = 0
while i < amount:
#这把第i个的值记录下来了
i = i + 1
#第i次循环sum需要加的值记为sum_add
sum_add = 0
for j in range(1, i+1):
sum_add = sum_add + j
sum += sum_add
print("最后的和是", sum)
# #下面的是我之前错误的代码
# #如果不用等差数列求和公式:
# #先求出要加的项,再求出前n项和
# amount = int(input("请输入需要输入的项:"))
# #我先找出第i次循环的最大值,每次最大值将前一次的求和加上本次的求和
# #第i次循环的最大值记作i
# i = 0
# #它的和记作sum
# sum = 0
# sum_add = 0
# while i < amount:
# #这把第i个的值记录下来了
# i = i + 1
# #第i次循环sum需要加的值记为sum_add
# for j in range(1, i+1):
# sum_add = sum_add + j
# sum = sum + sum_add
# print("最后的和是", sum) import sys def calc(n): result =0 for i in range(1,n+1): result += sum([j for j in range(1,i+1)]) return result for line in sys.stdin: a = line.strip() print(calc(int(a)))
n = int(input()) s = 0 for i in range(1,n+1): if i%2 == 0: s += (i//2+1)*i-i//2 else: s += (i//2+1)*i print(s)
n = int(input()) s = 0 for i in range(1,n+1): s += (i//2+1)*i + i//2*(i%2-1) print(s)