#include <iostream>
#include <queue>
#include <cstring>

#define PII pair<int,int> 
using namespace std;

const int N = 2e5 + 10;
int ne[N],e[N],h[N],idx;
int dx[N];
int n,m;

void add(int a,int b){
    e[idx] = b;
    ne[idx] = h[a];
    h[a] = idx ++;
}

bool bfs(int a,int b){
    queue<PII> op;
    op.push(make_pair(a,b));
    dx[a] = b;
    while(op.size()){
        auto pp = op.front();
        op.pop();
        int aa = pp.first;
        int bb = pp.second;
        for(int i = h[aa]; i != -1; i = ne[i]){
            int uu = e[i];
            if(dx[uu] == 0){
                op.push(make_pair(uu,3 - bb));
                dx[uu] = 3 - bb;
            }
            else{
                if(dx[uu] == bb) return 1;
            }
        }
    }
    return 0;
}

void solve(){
    memset(h,-1,sizeof h);
    cin >> n >> m;
    for(int i = 1; i <= m; i ++){
        int a,b;
        cin >> a >> b;
        add(a,b);
        add(b,a);
    }
    bool kk =true;
    for(int i = 1; i <= n; i ++){
        if(dx[i] == 0){
            if(bfs(i,1)) kk = false;
            if(kk == false) break;
        }
    }
    if(kk) cout << "Yes\n";
    else cout << "No\n";
    return;
}

int main(){
//  int t;
//  cin >> t;
//  while(t --)
    solve();
    return 0;
}