poj2000

简单题

#include <cstdio>

#define maxn 10005

int n, f[maxn];

void init()
{
    int i = 1;
    int x = 0;
    while (1)
    {
        for (int j = 0; j < i; j++)
        {
            x++;
            if (x > 10000)
                return;
            f[x] = f[x - 1] + i;
        }
        i++;
    }
}

int main()
{
    init();
    while (scanf("%d", &n), n)
        printf("%d %d\n", n, f[n]);
    return 0;
}