好久没来写题了，有很多原因，不多说了， 现在抓紧时间来开始刷题就行了。。。
Gold Coins
| Time Limit: 1000MS | Memory Limit: 30000K | |
| Total Submissions: 21467 | Accepted: 13457 |
Description
The king pays his loyal knight in gold coins. On the first day of his service, the knight receives one gold coin. On each of the next two days (the second and third days of service), the knight receives two gold coins. On each
of the next three days (the fourth, fifth, and sixth days of service), the knight receives three gold coins. On each of the next four days (the seventh, eighth, ninth, and tenth days of service), the knight receives four gold coins. This pattern of payments
will continue indefinitely: after receiving N gold coins on each of N consecutive days, the knight will receive N+1 gold coins on each of the next N+1 consecutive days, where N is any positive integer.
of the next three days (the fourth, fifth, and sixth days of service), the knight receives three gold coins. On each of the next four days (the seventh, eighth, ninth, and tenth days of service), the knight receives four gold coins. This pattern of payments
will continue indefinitely: after receiving N gold coins on each of N consecutive days, the knight will receive N+1 gold coins on each of the next N+1 consecutive days, where N is any positive integer.
Your program will determine the total number of gold coins paid to the knight in any given number of days (starting from Day 1).
Input
The input contains at least one, but no more than 21 lines. Each line of the input file (except the last one) contains data for one test case of the problem, consisting of exactly one integer (in the range 1..10000), representing
the number of days. The end of the input is signaled by a line containing the number 0.
the number of days. The end of the input is signaled by a line containing the number 0.
Output
There is exactly one line of output for each test case. This line contains the number of days from the corresponding line of input, followed by one blank space and the total number of gold coins paid to the knight in the given
number of days, starting with Day 1.
number of days, starting with Day 1.
Sample Input
10 6 7 11 15 16 100 10000 1000 21 22 0
Sample Output
10 30 6 14 7 18 11 35 15 55 16 61 100 945 10000 942820 1000 29820 21 91 22 98
Source
解题思路：
POJ 2000 简单的一道模拟题，只要加，判断sum>=n，就结束，然后记录上一个阶段的状态，用sum+=i*i,把他们联系起来，完事后，把那些属于第j个阶段的数字在
补上就行了。。可以说很水了、
代码：
# include<cstdio>
# include<iostream>
using namespace std;
int main(void)
{
int n;
while ( cin>>n )
{
long long ans = 0;
int sum = 0;
if ( n == 0 )
break;
int j;
for ( int i = 1;i <= n;i++ )
{
sum+=i;
if ( n <= sum )
{
j = i-1;
break;
}
}
//cout<<j<<endl;
for ( int i = 1;i <= j;i++ )
{
ans+=i*i;
}
int t = 0;
for ( int i = 1;i <= j;i++ )
{
t+=i;
}
ans+=(n-t)*(j+1);
printf("%d %ld\n",n,ans);
}
return 0;
}