#include <cstdio>
#include <algorithm>
struct node {
	int x,y,v;
}a[100005];
int n,m,p,q;
int main() {
	freopen("max.in","r",stdin);
	freopen("max.out","w",stdout);
	scanf("%d%d", &n, &m);
	for (int i = 1;i <= n;i++) scanf("%d%d%d", &a[i].x, &a[i].y, &a[i].v);
	int tmp = 0;
	for (int i = 1;i <= m;i++) {
		tmp = 0;
		scanf("%d%d", &p, &q);
		for (int i = 1;i <= n;i++) 
			if (a[i].x >= p && a[i].y <= q) tmp = std::max(tmp,a[i].v);
		printf("%d\n", tmp);
	}
	return 0;
}