#include<stdio.h>
void main()
{
	int n,i,j;
	int a[100000];
	
	scanf("%d",&n);
	while(n!=-1)
	{
		a[0] = 0;
		for(i=1;i<=n;i++)
		{
			a[i] = a[i-1] - i;
			if(a[i]<=0)
			{
				a[i] = a[i] + 2*i;
				continue;
			}
			j=0;
			while(j<i)
			{
				if(a[i]==a[j])
				{
					a[i] = a[i] + 2*i;
					break;
				}
				j++;
			}
		}
    	printf("%d\n",a[n]);
	    scanf("%d",&n);
	}
}

• 开大数组来看是否出现过 (479) ppp 2004-12-28 17:52:53