nyoj 2100 Graveyard Design

该题题意是国王要建一个墓地，给出一个面积，看看哪几个连续数字做正方形的边，面积加在一起刚好和给出的数字相等。

也就是给出一个数字，找出n段连续的数字，使这n段数字的平方和等于给出的数字。

用尺取法很容易就能做出来。

#include <iostream>
#include <vector>
using namespace std;
struct result {
long long count;
long long left;
long long right;
};
int main()
{
long long n;
while (cin >> n)
{
long long l = 1;
long long r = 1;
long long sum = 0;
long long sq = 0;
long long rcount;
result a;
vector<result> point;
while (true)
{
while (sum < n)
{
sq = r*r;
sum += sq;
r++;
}
if (sq > n)
break;
if (sum == n)
{
a.count = r - l;
a.left = l;
a.right = r;
point.push_back(a);
}
sum -= l*l;
l++;
}
cout << point.size() << endl;
for (rcount = 0; rcount != point.size(); rcount++)
{
cout << point[rcount].count << " ";
for (long long i = point[rcount].left; i != point[rcount].right; i++)
{
cout << i << " ";
}
cout << endl;
}
}
}