#include"stdio.h"
#include"algorithm"
using namespace std;
int main()
{
	int n,s,t,i,j;
	int a[20002];
	int count=0;
	scanf("%d%d",&n,&s);
	for(i=0;i<n;i++)
		scanf("%d",&a[i]);
	sort(a,a+n);
	j=n-1;
	for(i=0;i<n-1;i++)
	{
		if(a[i]>=s) break;
		while(a[i]+a[j]>s)
			j--;
		if(j<=i)
			break;
			count+=(j-i);
	}
	printf("%d\n",count);
	return 0;
}

• Re:16MS水过…… (449) treert 2010-10-18 09:08:08