#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ll long long int #define pb push_back #define rep(i,n) for(int i=0;i<(n);i++) #define REP(i,n) for(int i=1;i<=(n);i++) using namespace std; int mx8[] = {0,0,1,-1,-1,1,-1,1}; int my8[] = {-1,1,0,0,-1,-1,1,1}; int mx4[] = {1,-1,0,0}; int my4[] = {0,0,-1,1}; const int MOD = 1000000007; int main(){ int n, m; cin >> n >> m; bool ok = true; ll g = 0, T = 0; rep(i,m){ ll t, p; cin >> t >> p; T += t; if(abs(g-p) <= T) { g = p; T -= abs(g-p); } else{ ok = false; break; } } if(ok) cout << "Yes" << endl; else cout << "No" << endl; }