1797.
The Owl and the Fox
时间限制 1000 ms
内存限制 128 MB
Fox Mithra has finally learned the numbers and he is now familiar with the concept of ‘one’,
’two’, ‘three’ and also even ‘zero’, ‘minus one’, ‘minus two’ and so on. Really, an achievement
for such a small fox. He took the textbook and copied the integers from the book one by one
from the smallest to the biggest on the wall of his enclosure in the ZOO.
“Look, there is something wrong with your sequence on the wall”, said the owl who just landed
on the branch above Mithra’s head. “You should put 30 between 20 and 22, there.”
“Why?”
“Because the importance of a number is judged by the sum of its digits. 30 is therefore less
important than 22 and it is more important than 20. And obviously, 30 should be equally close
to 20 and 22 because its sum of digits differs only by one from both 20 and 22.”
“I see,” replied Mithra, “you are really clever. Can you help me please to rearrange the sequence
correctly? Each time I tell you a number N you will tell me the closest smaller number with
sum of digits less by one than the sum of digits of N.”
“With pleasure,” nodded the owl majestically.
Your task is to imitate the owl’s task. Given an integer N you have to find the biggest integer
which is smaller than N with sum of digits less by one than the sum of digits of N.
输入数据
输出数据
For each test case print on a separate line the number demanded by fox Mithra.
样例输入
复制
30
199
1000
1520
END \n
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样例输出
复制
20
198
0
1510 \n
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