#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define printVec(v) printf("{"); for (const auto& i : v) { std::cout << i << ", "; } printf("}\n");
#define degreeToRadian(deg) (((deg)/360)*2*M_PI)
#define radianTodegree(rad) (((rad)/2/M_PI)*360)
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
using namespace std;
using P = pair<int,int>;
using ll = long long;
const ll INF = 1LL<<60;
const int MOD = 1e9 + 7;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

//cin.tie(0);ios::sync_with_stdio(false);
//cout << fixed << setprecision(15) << y << endl;
int main() {
  int N, M;
  cin >> N >> M;
  vector<pair<ll, ll>> inf;
  rep (i, M) {
    ll T, P;
    cin >> T >> P;
    inf.push_back({T, P});
  }
  
  ll limit = 0;
  int current = 0;
  for (auto v : inf) {
    limit += abs(current - v.second);
    //printf("%lld to %lld : limit = %lld\n", current, v.second, limit);
    if (limit > v.first) {
      cout << "No" << endl;
      return 0;
    }
    limit = v.first;
    current = v.second;
  }

  cout << "Yes" << endl;
  
  return 0;
}