#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<functional>
#include<math.h>
using namespace std;
#define N (1000000000+7)
#define M (998244353)
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;
 
int main(void){
    int n,m;
    cin>>n>>m;
    int nt = 0,np = 0;
    bool flag = true;
    for(int i=0;i<m;i++){
        int t,p;
        cin>>t>>p;
        int d1 = t-nt;
        int d2 = min(abs(np-p),nt+n-p);
        if(d1<d2){
            flag = false;
        }
        else{
            nt = t;
            np = p;
        }
    }
    if(flag)cout<<"Yes"<<endl;
    else cout<<"No"<<endl;
}