Codeforces Round #372 (Div. 2) -- C. Plus and Square Root

直接找规律就可以打表
开始是2，+2后，变成4，开方变成2，等级为2， 2/2 = 1
然后2 + 172 = 36，开方后变成6 等级为3， 6/3 = 2
然后6 + 46 * 3 = 144，开方后变成12 等级为4 12/4 = 3
然后12 + 974 = 400 开方后变成20 等级为5， 20/5 = 4
那么第k项就是
(k（k+1） k * ( k + 1 ) - (k-1)k )/k = k(k+1)*(k+1) - k + 1
数据不会爆long long
ac代码 46ms

include<bits/stdc++.h>

using namespace std;
typedef unsigned long long ll;
const ll maxn = 100000 + 10;
ll ans[maxn];
ll ping(ll x)
{
return x(x+1)(x+1)-x+1;
}
void init()
{
ans[1] = 2ll;
for (int i = 2; i < maxn; ++i)
{
ll t = ping(i);
ans[i] = t;
}
}
int main()
{
init();
int n;
scanf("%d",&n);
for (int i = 0; i < n; ++i)
{
printf("%I64d\n",ans[i+1]);
}
return 0;
}