#include <bits/stdc++.h>
using namespace std;
inline int read(){
	int s = 0,f = 1;char c = getchar();
	while (!isdigit(c)){if (c == '-')f = -1;c = getchar();}
	while (isdigit(c)){s = (s << 3) + (s << 1) + (c ^ 48);c = getchar();}
	return s*f;
}
const int N = 1e5 + 5;
int n,m;
struct Splay{
	int root,idx;
	struct node{
		int s[2],val,p,tag,size;
	}tr[N<<1];
	void pushup(int x){
		tr[x].size = tr[tr[x].s[0]].size + tr[tr[x].s[1]].size + 1;
	}
	void pushdown(int x){
		if (tr[x].tag){
			tr[tr[x].s[0]].tag ^= 1;
			tr[tr[x].s[1]].tag ^= 1;
			swap(tr[x].s[0],tr[x].s[1]);
			tr[x].tag = 0;
		}
	}
	void rotate(int x){
		int y = tr[x].p,z = tr[y].p;
		pushdown(z);pushdown(y),pushdown(x);
		int k = (tr[y].s[1] == x);
		tr[y].s[k] = tr[x].s[k^1];
		tr[tr[x].s[k^1]].p = y;
		tr[x].s[k^1] = y;
		tr[y].p = x;
		tr[z].s[tr[z].s[1] == y] = x;
		tr[x].p = z;
		pushup(y);
		pushup(x);
	}
	void splay(int x,int k){
		while (tr[x].p != k){
			int y = tr[x].p,z = tr[y].p;
			if (z != k)
			    (tr[z].s[0] == y) ^ (tr[y].s[1] == x) ? rotate(y) : rotate(x);
			rotate(x);
		}
		if (!k)
		    root = x;
	}
	void insert(int v){
		int x = root,p = 0;
		while (tr[x].s[v > tr[x].val] && tr[x].val != v){
			p = x;
			x = tr[x].s[v > tr[x].val];
		}
		x = ++idx;
		tr[x].p = p;
		tr[p].s[v > tr[p].val] = x;
		tr[x].val = v;
		tr[x].tag = 0;
		tr[x].size = 1;
		splay(x,0);
	}
	int find(int val){
		int x = root;
		while (1){
			pushdown(x);
			if (val <= tr[tr[x].s[0]].size)
			    x = tr[x].s[0];
			else {
				val -= tr[tr[x].s[0]].size+1;
				if (!val)
				    return x;
				x = tr[x].s[1];	    
			}
		}
	}
	void reverse(int x,int y){
		x--,y++;
		int l = find(x),r = find(y);
		splay(l,0);
		splay(r,l);
		int node = tr[r].s[0];
		tr[node].tag ^= 1;
	}
	void query(int x){
		pushdown(x);
		if (tr[x].s[0])
		    query(tr[x].s[0]);
		if (tr[x].val != -2e9 && tr[x].val != 2e9)
		    printf("%d ",tr[x].val);
		if (tr[x].s[1])
		    query(tr[x].s[1]);
	}
}splay;
int main()
{
    n = read(),m = read();
    splay.insert(-2e9),splay.insert(2e9);
    for (int i=1;i<=n;i++)
        splay.insert(i);
    for (int i=1,u,v;i<=n;i++)
    {
    	u = read();v = read();
    	splay.reverse(u+1,v+1);
	}
	splay.query(splay.root);
	return 0;
}