离散化

\(code :\)

void lsh()
{	
	int s[maxn];
	for(int i=1;i<=n;++i) s[i]=a[i];
	sort(s+1,s+n+1);
	int tot=unique(s+1,s+n+1)-s-1;
	for(int i=1;i<=n;++i) a[i]=lower_bound(s+1,s+tot+1,a[i])-s;
}

借助\(s\)数组来离散化\(a\)数组