# encoding: utf-8
#
#m=input("请输入起始整数m=")
#n=input("请输入结束整数n=")
#k=input("请输入间隔k=")
m=1
n=11
k=2
sum=0
for i in range(m,n,k):
sum=sum+i
print(sum)
# encoding: utf-8
#
#m=input("请输入起始整数m=")
#n=input("请输入结束整数n=")
#k=input("请输入间隔k=")
m=1
n=11
k=2
sum=0
for i in range(m,n,k):
sum=sum+i
print(sum)