#include <cstdlib>
#include <cstdio>
#include <algorithm>
using namespace std;
const int MAXN=100100;
class Interval {public:int s,e,v;}q[MAXN];
int N,M,ans,x,y;

bool cmp(const Interval&a,const Interval&b)
{return a.s<b.s;}

inline void init()
{
	scanf("%d %d\n",&N,&M);
	for(int i=1;i<=N;i++) 
		scanf("%d %d %d\n",&q[i].s,&q[i].e,&q[i].v);
	sort(q+1,q+1+N,cmp);
}

inline int binary(int s)
{
	int l=1,r=N,mid,anss;
	while(l<=r)
	{
		mid=(l+r)/2;
		if(q[mid].s>=s) anss=mid,r=mid-1;
		else l=mid+1;
	}
	return anss;
}

inline int Max(int a,int b)
{
	return a>b?a:b;
}

inline void baori()
{
	int tmp;
	for(int i=1;i<=M;i++)
	{
		scanf("%d %d\n",&x,&y);
		tmp=binary(x); ans=0;
		for(int j=tmp;q[j].s<=y&&j<=N;j++)
		{
			if(q[j].e<=y) ans=Max(ans,q[j].v);
		}
		printf("%d\n",ans);
	}
}

int main()
{
	freopen("max.in","r",stdin);
	freopen("max.out","w",stdout);
	init();
	baori();
	return 0;
}